Running Head: LAB REPORT
LAB REPORT 8
Lab Report
Student Name
University Affiliation
Instructor’s Name
Introduction
Water safety and especially in terms of drinking is a subject that has come up recently. To promote good health among people in the world, there is need to ensure the consumption of clean water. Drinking water quality is a subject that has been investigated for a long period of time. Different studies has shown what constitutes drinking water that should be regarded as quality. A research was for instance conducted with an aim of studying the various chemical compounds of surface water, drinking water and groundwater and how they affect human health. To address this research, provisional drinking water guidelines values were used for 50 most common contaminants related to drinking water and the water cycle in general. For drinking water guidelines, the values were based upon literature of toxicological data. Concentration levels of chemicals in these waters were recorded and were then compared to the provisional guidelines. The study focused on two main river basins which were Meuse and Rhine. From the study, it was found out that compounds found in these river basins posed no appreciable concern to the health of the users (Schriks et.al, 2010). From study, it is very clear that there has been a need to ensure humans consume water that is safe or free from any harmful levels of contaminants.
The experiment was carried out with an aim of understanding whether there are benefits in consuming bottled water in comparison to the tap water. Generally, water contains various chemical compounds. It is, however, very important to note that bottled water normally undergoes certain purification levels in which the tap water is never subjected to. The experiment was thus conducted to identify whether drinking bottled water can be beneficial health wise in comparison to the direct consumption of tap water.
The hypothesis for this experiment was that if tap water straight from the faucet contains the most contaminants, then bottle water will have less added to them. This means that it is expected that bottled water will contain fewer contaminants when compared to tap water, once the experiment is conducted. This is the expected result as bottled water normally undergoes extra purification process compared to tap water.
Materials and Methods
Different contaminants were under investigation in this experiment. They included ammonia, chloride, phosphate, iron, pH and the 4 in 1 test that included total alkalinity, total chlorine and total hardness. Three different water samples were also used; they included tap water, Dasani bottled water and Fiji bottled water. The following were the materials used for this experiment: ammonia ...
Running Head WATER QUALITY AND CONTAMINATION1WATER QUALITY A.docxtoltonkendal
Running Head: WATER QUALITY AND CONTAMINATION 1
WATER QUALITY AND CONTAMINATION 7
Water Quality and Contamination
Brenda Rouse
SCI 207: Our Dependence upon the Environment
Instructor: Haleh Keshtkar
Date: August 17, 2017
Water Quality and Contamination
Introduction
Water is one of the most important factors for any animal’s survival (Teixeira, De Azevedo, Mendl, Cipreste, & Young, 2007). One could go for days without food, but could not last the same time without water. Therefore, everyone is often vulnerable to harmful organisms in the water, particularly when he or she is desperate enough for it. Notably, although about seventy percent of the earth’s surface is covered with water, a significant population of people does not have access to clean drinking water (Arheimer, 2016). In response to the demand, the government often avails alternatives to its citizens in the form of tap water, while investors make a more ambitious plan in providing bottled water.
Like any other business, the bottled water investors often seek to make a profit. On the other hand, tap water also comes at a price since the government running the program needs funds to maintain the purification and delivery systems (Whelton et al., 2015). Therefore, it is necessary that the consumers understand whether they get enough value for their money, based on the differences in prices of the different water sources. This experiment hopes to provide, with certainty, the differences between some of the most common sources of water in the household. Since its quality determines the price of a product, the differences in quality, in this case, will be based on the level of contamination.
If Dasani, Fiji, and tap water were tested for mineral components, then tap water would have the highest concentration of minerals, followed by Dasani, while Fiji would contain the least concentration of minerals. The difference would result from the fact that tap water goes through drainage pipes, which could at times be corroded, which adds to the minerals present in the water that could be absent in the Fiji and Dasani water (Dolnicar, Hurlimann, & Grün, 2014). Compared to Fiji, Dasani has more contaminants since I can often taste the minerals when I use the water.
Materials and Methods
To test for the presence of contaminants, different materials were necessary for recording and collection of the water utilized for the test process. We put the test strips in the water for duration of 5, 30, or 45 seconds determining which test was used and compared the strips to the chart after removing them from the water. This was repeated for the ammonia, phosphate, 4 in 1, iron and chloride tests. The charts provided a scale which would then determine the concentration of the iron in either of the Dasani, Fiji, and tap water samples. We then recorded the results on a table for each of the tests. The PH test included the use of jiffy juice, whose 5 ml was added to 25 ml of each of the water ...
WHAT’S IN YOUR WATERPreviousNextWe take for granted the water.docxphilipnelson29183
WHAT’S IN YOUR WATER?
PreviousNext
We take for granted the water we use to brush our teeth, wash our clothes and keep our lawns green. However, water is an extremely limited resource on the planet and we need to conserve and protect it from pollution. Today you will learn how the levels of chemicals (natural and added) are measured in different sources of water and learn whether they are a danger to your health.
LEARNING OBJECTIVES
In this laboratory you will learn:
· To identify what factors can contribute to water quality
· To use negative and positive controls to validate experimental results
· To use laboratory techniques to test for the presence of chemicals/molecules in our water
· To find other resources of information on water quality
ACTIVITIES
What you will do in lab today-
· Each pair of students will choose a sample of water to test
· Each pair of students will perform assays on their water sample to determine whether it contains iron, chlorine, ammonia, calcium or magnesium, nitrates and oxygen
· Each pair will report their results on their water sample
ASSESSMENTS
· Lab report (75): This is your first lab report of the semester – make sure you read the resources on writing a lab report and use the rubric – you can link to those here.
INTRODUCTION
PreviousNext
Water is a chemical (H2O) that all life depends on. It makes up about 60% of the human body and our cells and organ systems are dependent on its unique characteristics. It is an important solvent, which means that many things dissolve into it (see below for a short list). For example, table salt easily dissolves in water. Also, water naturally has a pH of 7, but when other chemicals are present the pH can change. When pH decreases, we call that acidic.
As human population grow, so do their needs for, including their need for water. Many researchers believe that in the next 20 years over half the world’s population will have a shortage of potable or drinkable water. Despite the fact that 75% of the surface of earth is covered in water, 97% is salt water in the oceans and another 2% is frozen in glaciers, leaving us with less than 1% to use. Scientists hope to develop methods to increase potable water using desalination techniques, but in the meantime we have to take care not to contaminate or pollute our current drinkable water sources.
Toxins in the water are absorbed or consumed by primary producers and primary consumers – those “low”on the food chain – like bacteria, algae, protists and invertebrates. As toxins are transferred “up the food chain” or from one trophic level to the next, they are concentrated and become even more toxic to the organism. This phenomenon is called bioaccumulation or biologic magnification (Figure 1). This is one reason that humans need to be concerned about pollution in natural rivers and lakes in addition to our public drinking water.
Figure 1. Bioaccumulation or biomagnification. The accumulation of a chemical (in this case the + s.
Running Head: LAB REPORT
LAB REPORT 8
Lab Report
Student Name
University Affiliation
Instructor’s Name
Introduction
Water safety and especially in terms of drinking is a subject that has come up recently. To promote good health among people in the world, there is need to ensure the consumption of clean water. Drinking water quality is a subject that has been investigated for a long period of time. Different studies has shown what constitutes drinking water that should be regarded as quality. A research was for instance conducted with an aim of studying the various chemical compounds of surface water, drinking water and groundwater and how they affect human health. To address this research, provisional drinking water guidelines values were used for 50 most common contaminants related to drinking water and the water cycle in general. For drinking water guidelines, the values were based upon literature of toxicological data. Concentration levels of chemicals in these waters were recorded and were then compared to the provisional guidelines. The study focused on two main river basins which were Meuse and Rhine. From the study, it was found out that compounds found in these river basins posed no appreciable concern to the health of the users (Schriks et.al, 2010). From study, it is very clear that there has been a need to ensure humans consume water that is safe or free from any harmful levels of contaminants.
The experiment was carried out with an aim of understanding whether there are benefits in consuming bottled water in comparison to the tap water. Generally, water contains various chemical compounds. It is, however, very important to note that bottled water normally undergoes certain purification levels in which the tap water is never subjected to. The experiment was thus conducted to identify whether drinking bottled water can be beneficial health wise in comparison to the direct consumption of tap water.
The hypothesis for this experiment was that if tap water straight from the faucet contains the most contaminants, then bottle water will have less added to them. This means that it is expected that bottled water will contain fewer contaminants when compared to tap water, once the experiment is conducted. This is the expected result as bottled water normally undergoes extra purification process compared to tap water.
Materials and Methods
Different contaminants were under investigation in this experiment. They included ammonia, chloride, phosphate, iron, pH and the 4 in 1 test that included total alkalinity, total chlorine and total hardness. Three different water samples were also used; they included tap water, Dasani bottled water and Fiji bottled water. The following were the materials used for this experiment: ammonia ...
Running Head WATER QUALITY AND CONTAMINATION1WATER QUALITY A.docxtoltonkendal
Running Head: WATER QUALITY AND CONTAMINATION 1
WATER QUALITY AND CONTAMINATION 7
Water Quality and Contamination
Brenda Rouse
SCI 207: Our Dependence upon the Environment
Instructor: Haleh Keshtkar
Date: August 17, 2017
Water Quality and Contamination
Introduction
Water is one of the most important factors for any animal’s survival (Teixeira, De Azevedo, Mendl, Cipreste, & Young, 2007). One could go for days without food, but could not last the same time without water. Therefore, everyone is often vulnerable to harmful organisms in the water, particularly when he or she is desperate enough for it. Notably, although about seventy percent of the earth’s surface is covered with water, a significant population of people does not have access to clean drinking water (Arheimer, 2016). In response to the demand, the government often avails alternatives to its citizens in the form of tap water, while investors make a more ambitious plan in providing bottled water.
Like any other business, the bottled water investors often seek to make a profit. On the other hand, tap water also comes at a price since the government running the program needs funds to maintain the purification and delivery systems (Whelton et al., 2015). Therefore, it is necessary that the consumers understand whether they get enough value for their money, based on the differences in prices of the different water sources. This experiment hopes to provide, with certainty, the differences between some of the most common sources of water in the household. Since its quality determines the price of a product, the differences in quality, in this case, will be based on the level of contamination.
If Dasani, Fiji, and tap water were tested for mineral components, then tap water would have the highest concentration of minerals, followed by Dasani, while Fiji would contain the least concentration of minerals. The difference would result from the fact that tap water goes through drainage pipes, which could at times be corroded, which adds to the minerals present in the water that could be absent in the Fiji and Dasani water (Dolnicar, Hurlimann, & Grün, 2014). Compared to Fiji, Dasani has more contaminants since I can often taste the minerals when I use the water.
Materials and Methods
To test for the presence of contaminants, different materials were necessary for recording and collection of the water utilized for the test process. We put the test strips in the water for duration of 5, 30, or 45 seconds determining which test was used and compared the strips to the chart after removing them from the water. This was repeated for the ammonia, phosphate, 4 in 1, iron and chloride tests. The charts provided a scale which would then determine the concentration of the iron in either of the Dasani, Fiji, and tap water samples. We then recorded the results on a table for each of the tests. The PH test included the use of jiffy juice, whose 5 ml was added to 25 ml of each of the water ...
WHAT’S IN YOUR WATERPreviousNextWe take for granted the water.docxphilipnelson29183
WHAT’S IN YOUR WATER?
PreviousNext
We take for granted the water we use to brush our teeth, wash our clothes and keep our lawns green. However, water is an extremely limited resource on the planet and we need to conserve and protect it from pollution. Today you will learn how the levels of chemicals (natural and added) are measured in different sources of water and learn whether they are a danger to your health.
LEARNING OBJECTIVES
In this laboratory you will learn:
· To identify what factors can contribute to water quality
· To use negative and positive controls to validate experimental results
· To use laboratory techniques to test for the presence of chemicals/molecules in our water
· To find other resources of information on water quality
ACTIVITIES
What you will do in lab today-
· Each pair of students will choose a sample of water to test
· Each pair of students will perform assays on their water sample to determine whether it contains iron, chlorine, ammonia, calcium or magnesium, nitrates and oxygen
· Each pair will report their results on their water sample
ASSESSMENTS
· Lab report (75): This is your first lab report of the semester – make sure you read the resources on writing a lab report and use the rubric – you can link to those here.
INTRODUCTION
PreviousNext
Water is a chemical (H2O) that all life depends on. It makes up about 60% of the human body and our cells and organ systems are dependent on its unique characteristics. It is an important solvent, which means that many things dissolve into it (see below for a short list). For example, table salt easily dissolves in water. Also, water naturally has a pH of 7, but when other chemicals are present the pH can change. When pH decreases, we call that acidic.
As human population grow, so do their needs for, including their need for water. Many researchers believe that in the next 20 years over half the world’s population will have a shortage of potable or drinkable water. Despite the fact that 75% of the surface of earth is covered in water, 97% is salt water in the oceans and another 2% is frozen in glaciers, leaving us with less than 1% to use. Scientists hope to develop methods to increase potable water using desalination techniques, but in the meantime we have to take care not to contaminate or pollute our current drinkable water sources.
Toxins in the water are absorbed or consumed by primary producers and primary consumers – those “low”on the food chain – like bacteria, algae, protists and invertebrates. As toxins are transferred “up the food chain” or from one trophic level to the next, they are concentrated and become even more toxic to the organism. This phenomenon is called bioaccumulation or biologic magnification (Figure 1). This is one reason that humans need to be concerned about pollution in natural rivers and lakes in addition to our public drinking water.
Figure 1. Bioaccumulation or biomagnification. The accumulation of a chemical (in this case the + s.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
1. Coacervates Experiment
The purpose of this lab was to investigate how the concentration of ammonia affects the formation
of coacervates. It was hypothesized that as the ammonia concentration increase, so will the number
of coacervates until it reaches the optimal state, then would start to decrease. For this experiment 4
mL of gum arabic solution (carbohydrate) was mixed with a gelatin solution (protein) and was
placed under a microscope to observe the number of coacervates. According to Oparin, combining
organic macromolecules would create coacervates. The first run was the control so no ammonia was
added but after each run, 2 drops of ammonia was added to see its effect of coacervates. On run 1,
49 coacervates was recorded. This data confirmed Oparin's theory ... Show more content on
Helpwriting.net ...
Another error could be the small sample space. Only vial was tested so the data is not very reliable.
If more vials were tested, it could help disprove the mistake of this experiment or confirm it by
making it more legitimate with consistent results. The unequal amount of solution on each
microscope slide could also be an error. Even though only 1 drop of solution was dropped onto the
slide each run, the pipets are not precise and could lead to some drop being bigger than other. The
bigger drop would have more coacervates than the smaller drop. This could make the data less
reliable since a variable was added which makes it harder to understand the effect of ammonia on
the formation of coacervates. Understanding the impact of chemicals in the atmosphere and the
presence of water is very important in identifying life. Scientists are currently observing other
planets in the universe and determine their potential to sustain life by studying the planet's
atmospheric makeup. By comparing its atmosphere to Earth's atmosphere, scientists can determine
if life exist on a distant planet without going there
... Get more on HelpWriting.net ...
2.
3. Pollution Analysis of River Running through a Community
Contents:
1. –Environmental issue
–Hypothesis
–Aim
–Apparatus
–Method
2. –Variables: Controlled
Independent
Dependent
–Results: Table
Bar Graph
3. –Conclusion
–Evaluation
4. –Article with proposed solutions
5. –Continuation of Article
6. –Bibliography
This document includes a cover page and attached Plagiarism report.
Human activities generate many different forms of pollution that are harmful to our environment, for
example; water pollution. Pollutants change the pH balance of the water sources they infest, which
in large cases is dangerous to the plants and animals that both live in that water source and rely on it
for survival. Industrial activities such as mining and manufacturing produce waste that make the pH
balance of water acidic, while in suburban areas the waste produced and the activities that affect the
water sources generally make the water more alkaline.
This investigation will determine whether a river running through the local suburban area is being
polluted by the community, its occupants, and their regular lifestyles or not.
Hypothesis: The water in the river running through a suburban area is more polluted with alkaline
substances than acidic substances.
Aim: to investigate whether the water in the river running through a suburban area is more polluted
with alkaline substances than acidic substances.
Apparatus:
Six containers for different water samples
Two droppers
Chlorine neutraliser –found in a fresh water test kit
Solution 4 (pH test
6. Hardness And What Impact Does It Have On Water Quality
1. What is hardness and what impact does it have on water quality?
Hardness is the amount of dissolved calcium and magnesium in the water. Hardness impacts on
water quality throughout the aesthetic acceptability by consumers (meaning the concentration of the
calcium and magnesium and other dissolved solids are measureable by the consumers). In addition
to, economic and operational considerations (which is controllable throughout the treatment or
blending in public drinking water), hard water tends to leave scale deposition in the water
distribution system, as well as in heated water applications. (Hardness in Drinking–water, 2011).
2. What water quality standards are associated with water hardness?
There is no Primary or Secondary standard for water hardness by EPA. Also hardness has no health
risk. As the hardness of water is classified: 0 to 60 mg/ as calcium carbonate is classified as soft; 61
to 120 mg/L as moderately hard; 121 to 180 mg/L as hard; and more than 180 mg/L as very hard.
(Water–quality criteria. (n.d.).
3. Briefly describe your understanding about pH and why is pH important in water treatment. Give
two examples. pH is a measure of the hydrogen ion activity in the water and is determined by the
relative number of the hydrogen ions for acidity and hydroxide ion for alkalinity, thus
mathematically expressed as pH=–log [H+] where [H+] is the hydrogen ion activity . pH values are
calculated in powers of 10.Thus, the hydrogen ion concentration of a solution
... Get more on HelpWriting.net ...
7.
8. The Depth Of The River Affect Its Overall Ph From Mid July...
Question: Does the depth of the river affect its overall pH from mid december 2015– to early
january 2016?
Knowledge Probe: According to.epa.gov/acidrain/measure/pH.html, pH is a measure of the
hydrogen ion concentration of a solution. Solutions with a high concentration of hydrogen ions have
a low pH and solutions with a low concentrations of H+ ions have a high pH. A pH of 7 is the most
neutral you can get and 0 being the most acidic and 14 being the most basic. each level is 10 times
more basic/ acidic than the previous level, for example a pH of 8 is 10 times more basic than 7, and
a pH of 9 is 100 times more basic than 7. when an acidic substance reacts with a basic substance
they counter each other like mixing hot and cold water. ... Show more content on Helpwriting.net ...
The blue bar grapH below it shows the pH of each of the 12 trial collected. The table below
compares the depth in inches to the pH directly, and the average of each is at the bottom of the table.
Data Analysis: On trial 5 something interesting happened where it did not match the trend of other
data points. you can see this when comparing the depth to pH with the grapHs; for example trial 1's
depth and pH is lower than trial 2's depth and pH, and trial 2's depth and pH is lower than trial 3's
depth and pH etc. that sort of trend is fluent through the data except trial 5 where depth was lower
than the previous trials but the pH was the highest collected. My data is accurate to a point but when
collecting the depth of the river it presented a challenge to get 100% accurate because it is
constantly changing; also the pH scale only measures to the hundredth of a digit. The pH Scales
calibration could also have been of slightly but all of my trials were collected under the same
calibration so it does not seem to present a change in trend but instead with the actual numbers.
Claim: When the depth on the Looking Glass river was higher it had a higher pH in late december
2015 to early January 2016.
Data Supporting Claim: When analysing my data you can clearly see that when the
... Get more on HelpWriting.net ...
9.
10. Cardiovascular Regulation Of Plasma Volume
In order to study the kidney 's regulation of plasma volume, osmolality, and pH, the changes in urine
flow rate, specific density, and urine pH of adult human subjects were measured. Subjects were
assigned one of four beverage options: water, Gatorade, Coke, or nothing. Beverages of different
compositions were used to study what effects does fluid intake have on urine volume and
composition. Subjects fasted five hours prior to the experiment, in which the subjects were required
to void and test their own urine every thirty minutes for 120 minutes after ingesting the beverage
they were assigned. The urine volume, specific gravity, and urine pH were measured for each void.
The subjects were instructed to fast five hours prior to the experiment and were allowed to drink
only eight ounces of water if necessary (Manuguid et al., 2015). Avoiding food or drink rendered the
subjects in a similar physiological state at the start of the experiment. This is important because the
consumption of food or drink shortly before the experiment may affect the volume and composition
of the urine voided, which would have affected the results. If a subject had ingested a considerable
amount of fluid an hour before the experiment, their urine volume for their first void could have
been greater than expected. The amount of liquid the subjects ingested depended on their body
weight. As a result, the amounts of liquid ingested varied within the drinking groups. At T0, the
subjects were in a state of
... Get more on HelpWriting.net ...
11.
12. Essay on SCI 207 Week 4 Lab
Charles Jacquier Lab 4 – Energy Sources and Alternative Energy SCI 207 Professor Selhorst
Experiment 1: The Effects of Coal Mining Table 1: pH of Water Samples Water Sample Initial pH
Final pH (24–48 hours) Pyrite 5 5 Activated Carbon 5 7 Water 5 5 POST LAB QUESTIONS 1.
Develop hypotheses predicting the effect of pyrite and coal on the acidity of water? a. Pyrite
hypothesis = If pyrite is added to water, it will make the water more acidic. b. Coal hypothesis = If
the activated carbon is added to the water, it will make the water more acidic. 2. Based on the results
of your experiment, would you reject or accept each hypothesis that you produced in question 1?
Explain how you determined this. a. ... Show more content on Helpwriting.net ...
Based on the results of your experiment, would you reject or accept each hypothesis that you
produced in question 1? Explain how you determined this. Direct vs indirect accept/reject
=Rejected. The motor was just as fast when the solar panel was set up at a 45 degree angle Direct vs
reflected accept/reject = Accepted. When the foil was reflected at the solar panel, the motor moved
faster. Direct vs shaded accept/reject = At 25% shading–Rejected–The motor moved just as fast as
when the solar panel was completely exposed to sunlight. At 50%–Accepted–The motor moved
slower than when the solar panel was completely exposed to sunlight (speed medium to fast) At
75%–Accepted–The motor moved very slow compared to when the solar panel was completely
exposed to sunlight (Very slow) Direct vs filtered accept/reject = Rejected–Upon being covered by
the red, yellow, green, and blue cellophane, the motor moved the same as in direct sunlight 3. Does
increased exposure to the sun's light produce more current? Explain how you know this based on
your data. Answer = YES. The more exposure the solar panel had to the sun, the faster the motor
moved. Through a variety of trials with the solar panel and exposure to the sun, it was determined
that the more exposure the solar panel had, the
... Get more on HelpWriting.net ...
13.
14. Meat Tenderness, And Consumer Perceptions
Meat Tenderness, and Consumer Perceptions
Introduction The current climate of the relationship between the food–producing industry and
consumers is volatile. Current self–appointed consumer leaders such as Vani Hari, known as the
"Food Babe" (foodbabe.com) pressure food industry sectors for changes in products. Reasoning for
these changes largely reside in the practices of fear–mongering, using terminology outside the
knowledge of the readers these leaders attract, exacerbating worst–case scenarios without full
disclosure of required toxic– or lethal–doses. Common consumer concerns have migrated into the
meat products industry. Consumers often demand livestock animals used for meat production to be
raised similarly to their ... Show more content on Helpwriting.net ...
Post–exsanguination, the cellular processes continue to be active until an environmental or
substrate–level limitation ceases operation. Koohmaraie et al. (1987) suggested that all animals prior
to slaughter are equally tender. Differences in tenderness level therefore, are a result of the process
of harvest, and the conversion of muscle to meat products. The first 24 hours following slaughter
includes many events that are decisive in the resulting tenderness of meat products. During this
time, energetic biological processes result in decreasing pH within the meat. Muscle rigor delay
phase and onset phase occur, as well as heat dissipation and resultant carcass cooling. Each of these
various factors greatly impact meat quality. pH Changes. The pH of living muscle is 7.0; literature
suggests that final post–slaughter pH ranges from 5.3 – 5.8 (Smulders et al., 1992; Yu et al., 2008).
The decline of muscle pH during the conversion of muscle to meat carries importance to both meat
quality as well as a bacterial growth inhibitor. Ultimate pH in beef carcasses may be reached from
24 – 40 hours post–mortem (Savell et al., 2005). The decline of pH is a direct result of adenosine
triphosphate (ATP) production maintained in muscle through the anaerobic energy production
system: glycolysis. As blood–loss is completed via exsanguination, the ability to maintain oxygen as
the terminal electron acceptor for aerobic ATP production fails
... Get more on HelpWriting.net ...
15.
16. Essay about Acid/ Base properties of an antimicrobial agent
Chem 253
Lab 1: Acid/Base Properties of an Antimicrobial Agent
09/03/13
Purpose The purpose was to determine the acid and base properties of the antimicrobial agent
sodium benzoate. Theory Sodium has mainly been used in food processing to avoid growth of
bacteria and harmful microorganisms. It is commonly used to preserve foods and beverages that
have an acidic pH. Rather than benzoic acid, sodium benzoate is used because it is generally soluble
in most aqueous solutions but benzoic acid is not.
Reaction Sodium benzoate mixed with water, dissociates into benzoate and sodium ions.
Hydrogen chloride, which is a gas, will exist in ionized form when combined with water to form
hydrochloric acid.
Then when ... Show more content on Helpwriting.net ...
Moisten the filter paper in the funnel with a little distilled water, and make sure that the moist filter
paper fits snugly in the bottom of the Buchner funnel with no folds or bends in the filter paper
visible. Use the thick rubber tubing from your drawer to provide vacuum from the "aspirator" to
your "filter flask." Be sure you are connecting the tubing to the "aspirator," not to the water or gas
outlet. Turn on the water to a low volume to create a vacuum in the filter flask but not so much that
you flood the sink.
6) Transfer the crystals (quantitatively) from Step 4 to the funnel. Use about 5 mL of distilled water
to rinse any solid that remains in the beaker onto the filter paper. Let the solid air–dry with the
aspirator running for a few minutes.
7) Place the filter paper with solid in the oven for about 15 minutes to dry. Weigh and then dry again
for 5 minutes. Weigh again. If your second weight differs from the first weight by more than 0.5%,
dry again for 10 minutes. Continue this process until successive weighing's are within 0.5%.
For this lab, we must be sure to always wear our safety glasses whenever we are in the laboratory
and wear gloves when we are conducting an experiment. Benzoic acid and sodium benzoate used in
this experiment can be mild irritants to the skin. We must be careful not to get them on our skin or
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17.
18. Enzyme Lab Report On Hydrogen Peroxide
Enzyme Lab Report
Hydrogen peroxide is a toxic byproduct of cellular functions. To maintain hydrogen peroxide levels
the catalase enzyme deconstructs hydrogen peroxide and reconstructs the reactants into oxygen gas
and water. The catalase enzyme is found inside cells of most plants and animals. Regulating the
levels of hydrogen peroxide is crucial in homeostasis and analyzing it's optimal conditions for
performance is just as important. To understand the optimal environment for this enzyme, they are
put into different environments based off protein activity (enzymes are proteins). Catalase samples
will be put into different hydrogen peroxide environments based off pH and temperature. The more
active the enzyme, the more oxygen and water it will produce. Enzyme activity can be seen through
the release of oxygen in the hydrogen peroxide. Since oxygen cannot be accurately measured, the
data will consist of the longevity of the reaction in different environments. If the pH is higher than 7,
then the reaction rate will increase due to the ample amount of hydrogen ions in the hydrogen
peroxide. However the pH level cannot be higher than 10 or else there will be too many hydrogen
atoms in the peroxide for the enzyme to be able to deconstruct them. If the temperature is increased,
then the reaction rate will increase due to the ample amount of energy and movement in the
hydrogen peroxide and enzyme.
Materials:
This investigation requires:
Juiced potato (catalase solution)
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19.
20. Determining The Ph Of Household Items
Determining the pH of Household Items
March 22, 2016: Sara, Sam
Introduction: Everyday household items can be seen as just "household items". However, it is often
not realized that we could actually determine the pH very easily. It could also be important to know
the pH in everyday life. For example, it is important to keep track of human pH levels. Some people
are curious to see the pH of their own body, which is a great use to keep acidic levels leveled.
Another use in real life is determining the pH of pools. Whether it's your own or a public pool, pH
indicators come in hand to make sure the pool is sanitary and safe. pH indicators are indicators that
contain halochromic synthetic compound which is added to a solution so that it can be ... Show more
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An example would be pure water. Most of the time the pH is determined by pH paper but there are
also other ways to determine the pH. For example, in this lab, cabbage juice was used. Cabbage
juice is a great pH indicator because it can be homemade and easy to access.
Purpose/Hypothesis: The purpose of this experiment is to use both cabbage juice and pH paper to
determine the pH of household items. This way, we can tell which products are basic and which one
are acidic. If we use cabbage juice as an universal pH indicator by comparing it to pH paper then pH
determined by the cabbage juice will be unstable because by using cabbage juice, it can be different
depending on how diluted it is.
List of Materials needed:
1 drop bottle of cabbage juice
Beakers (depending on how many items)
pH paper
Spot plate(s)
Household products (Dish detergent, coffee, laundry detergent, milk, tap water, etc)
Procedure:
1. In order to find the pH of each household item by using pH paper, the pH paper was placed on the
drop plate. Using the dropper, start by having the household item dropped onto the pH paper.
Immediately observe in order to spot any colour changes on the pH paper. To determine the pH by
using the pH scale and record the pH on your table of observations. Depending on what the pH is, it
could be very acidic, basic or neutral. Repeat these steps for the other products.
2. The second step in this lab is to use
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21.
22. Coal Seam Gas
Coal seam gas (CSG) is mostly composed of methane and is typically attached to coal underground.
This gas is released when pressure on the coal seam is reduced by removing water from the seams
(Queensland Government, 2014 ). In order to obtain the gas, wells are drilled into the coal seams,
bringing water from the coal seams to the surface. This process reduces pressure and allows the gas
to be released (Queensland Government, 2014 ). CSG is an important energy resource in
Queensland and production of this gas takes up an ever–increasing proportion of Queensland gas
use. Almost every farmer in Queensland depends at times on underground water. The effect of CSG
extraction using underground fracturing on underground water is not clear. Basic sets of impacts that
are broadly well understood are that aquifer levels will sink dramatically and will depressurise. It
also risks groundwater contamination and the salt that is present in the water of coal seams will be
brought to the surface as well, in a quantity of about 1.8 million tonnes of salt per year (ABC, 2010).
There are several types of water contamination that are possible. One is through the injection of
chemicals through the fracking processes, which will go underground and can travel to nearby water
systems that are in use (Gasfield Free Northern Rivers, 2014). Another is through chemicals that
naturally exist in coal seams being taken out of the coal seams and exposed to other the various
water systems nearby. Some of
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23.
24. An Unknown Grignard Reagent Experiment Essay
Grignard
5. Introduction In this experiment, an unknown Grignard reagent was prepared from an aryl halide.
The unknown reagent was then reacted with carbon dioxide to form a carboxylic acid. The solid acid
was then isolated and recrystallized before the melting point was taken. The precipitate was then
dissolved in water and titrated to determine the molecular weight. The melting point and molecular
weight were then used to determine the unknown acid obtained from the experiment.
6. Data and Results The product obtained had a melting point of approximately 107 °C and a weight
of .324 grams. Some of the product would not dissolve in water and so was removed through
vacuum filtration, which left .141 g not dissolved in solution. It took 13.2 mL of sodium hydroxide
to turn the solution of the product dissolved in water pink. A molecular weight of 138.63 g/mol was
calculated from the data. These results indicate that the product was 2–methylbenzoic acid, the
Grignard reagent was 2–methylphenylmagnesium bromide, and the unknown bromide solution was
2–methylbromobenzene. Calculations showed that the limiting reagent of the Grignard preparation
was magnesium and that the experiment had a 23.13 % yield. 7. Discussion and Conclusion
Organometallic compounds, such as Grignard reagents, are molecules containing carbon–metal
bonds and are often used to create new carbon–carbon bonds. Grignard reagents–or
organomagnesims– are specifically those that have a carbon–magnesium bond.
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25.
26. The Effect Of Temperature And Ph Levels On Enzyme Activity
Joshua Kwon
Sep 19, 15
Biology p 4
How Do Changes in Temperature and pH Levels Affect Enzyme Activity? Lab Report
In biology class, we've learned that sugars produce energy and to use sugars to gain energy, an
organism needs a proper enzyme should exist to break it down the chemical bonds of the sugar.
Enzymes and proteins are important in organisms because they are involved in most chemical
reactions that take place inside of an organism. Our example of an important enzyme was catalase,
which breaks down H2O2. H2O2 is a natural by–product and toxic. When H2O2 contacts catalase,
it breaks down into water and oxygen. Our group got curious about how changes in temperature and
pH levels affect enzyme activity. Since enzymes are group of protein and protein can break easily by
acid, base, and hot temperature. To experiment our question, we used catalase solution, 3% H2O2
solution, 0.1 M HCl solution, 0.1 M NaOH solution, a beaker, an O2 gas sensor, sensor interface on
a Chromebook, pH paper, and safety gloves. Therefore, we conducted experiments to test how
enzyme activity in different conditions. Plus, we predicted that if temperature increases or enzyme
have contacts with acid or base, enzyme activity will decrease. We held four controlled experiments
which are controller, temperature, HCl Acid, and NaOH Base. We controlled the amount of catalase
to 10 mL and H2O2 solution to 4 mL. First we mixed catalase with H2O2 solution and used O2
sensor to gather
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27.
28. Effects of Acidic Depositon
The graph shows the pH value of acid rain water affecting crops in Vietnam. The two bar charts
represent two different places in Vietnam: Hoa Binh and Ha Noi. The graph proves that the
frequency of rain with below a pH of 5 is more frequent than above 5. This pH value results in the
crops growing less.
Like Vietnam, Canada is also facing issues with acidic deposition. A case study done by un.org
claims that 'The North American Maple is dying at a rate of 2.3% for each 100 exceedance units due
to the loss of calcium and other nutrients from soils. Lakes and streams are also remaining too acidic
or are not recovering to the point where they cannot support sensitive fish and aquatic biota. The
result is aquatic ecosystems that are unable to support a variety of species; therefore, biodiversity
continues to remain below pre–acidification levels."
After reviewing different examples of how pH affects other types of plants and seeds and the
scientific information of acid rain, it is now clear that the optimum pH for plant growth is between
5.5 and 7. It is also evident that acidic solution affects the growth rate, in which the pH's with a low
value slow down the growth process. There were a low number of seeds germinated in the pH of
1.65 and 2.11 due to the fact that seeds do not germinate efficiently at acidic solutions. However,
they do germinate at solutions of between 5.5 and 6.5. There is a chance that there was a decline at
pH 5 (the anomaly) due to the fact that it could
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29.
30. Where Does Taurine Come From Essay
Where Does Taurine Come from?
If you are wondering what makes energy drinks work, you may find ingredients like taurine as an
important component of these beverages. Taurine is found in products like Red Bull and many
energy drinks. What is it and where does taurine come from? Taurine is an amino acid that contains
sulphur, a molecule that is not found in many proteins. This amino acid helps increase muscle
function, aids performance and sports endurance, and helps regulate blood sugar levels, reduce
anxiety, and improve cardiac health. Although taurine is found in bull semen or bile, commercial
products that contain taurine uses lab–synthesized taurine, which is safe and suitable for people who
want to avoid using animal products.
Part 1: ... Show more content on Helpwriting.net ...
It also helps in the development of mental function in children. Research shows that taurine, when
paired with caffeine, improves reaction time and reduces sleepiness in sleep–deprived people.
Part 3: Is Taurine in Energy Drinks Safe?
Now that you know the answer to where does taurine come from, you probably also want to know if
it is safe to use. In small doses (up to 3,000 mg per day) supplemental taurine is considered safe. It
is therefore important to observe moderation in taking energy drinks containing taurine. For
example, Red Bull contains approximately 1000 mg of taurine per 8 oz can. So if you consume
more than 3 cans of this product per day and also eat meats and dairy products containing taurine,
you are likely to exceed the daily recommended amount.
Possible Side Effects of Taurine in Energy Drinks
Heavy or long–term use of taurine may have side effects. One study found that it can lower heart
rate. Mixing alcoholic drinks and taurine could lead to dehydration and abnormal heart rates, since
they are both diuretics. Other side effects include increased stomach acid and diarrhea. People with
bipolar disorder should avoid taking too much taurine since it may exacerbate their
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31.
32. Why Are My Fish Dying? Lab
Why Are My Fish Dying? Lab Jillian Jeffries Cadiz Marine Eco Period 4 November 19'th, 2014
Purpose: The purpose of this lab is to identify the element that is causing the fish in the Halibut tank
to die, by testing each variable between both of the identical tanks. Background Information: To
truly understand the cause of this awful fish mortality crisis in the HAGS Company, it is essential
that we gather all the information we can about the normal living conditions of both the Halibut and
Grunion fish. Halibut or Hippoglossus, is a flatfish from the family of the right–eye flounder fish,
the largest of all the flatfish, and can grow to more than 8 ft long and 700 lbs. They usually reside in
the North Pacific and the North Atlantic oceans, and are a readily enjoyed food all around the world.
Physically, they are dark brown on the top side with a cream underbelly and have very small scales
embedded within their skin.This color scheme is a form of countershading and disguises Halibut
from above and from below by blending into the light above and the ocean floor below
simultaneously. Halibut live at depths from nearly 10–100 meters, yet spend most of their time near
the bottom, they can often move up the water column to feed.Younger Halibut, up to 10 years of
age, are highly migratory, and generally migrate in a clockwise direction. Relatively inactive yet
strong swimmers, able to eat a large variety of fish such as cod, crab, and shrimp. Adult Atlantic
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33.
34. The Effects of Exercise on the Pulmonary Ventilation Rate
Respiration is the process that takes place in every living cell to make energy available to the body.
Energy is vital for us to carry out many life processes such as movement and so respiration in
essential to life. During respiration glucose and oxygen are used in a reaction that produces energy
and gives out carbon dioxide and water as waste products. Glucose is obtained by digestion of food
and oxygen is taken from the air during a process called breathing or ventilation. Pulmonary
Ventilation is the term given to the movement of air in and out of the lungs; the rate of pulmonary
ventilation is defined as the tidal volume multiplied by the number of breaths taken per minute.
Tidal volume is the volume of air breathed in or out during ... Show more content on
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The inspiratory system sends an impulse to the muscles of inspiration – the diaphragm and the
external intercostals muscles – and the stimulation of these muscles causes us to breathe in. As the
lungs expand due to inspiration this change is detected by pressure receptors of stretch receptors
which then stimulate the expiratory centre, which then stimulates the muscles of expiration – the
diaphragm and the internal intercostals
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35.
36. Osmosis Egg Lab
Table 2. Shows the 10 groups results of the rate of change in g/s with the average rate displayed
along with the standard deviation. As shown the average rate is within negative 0.000293 and
positive 0.001740. From this table we can confirm that there have not been outliers in the results,
outliers could come down to the results of errors on the practical. These errors could be caused by
incorrect use of equipment, fluctuations in the solution or difference in eggs used. At a zero
concentration the average was 0.001740, when increasing the solution by one percent the average
revealed a decrease by 0.00084. From two percent to five percent it increased by 0.00074, this
shows that between the concentration of two and five percent the egg and solution had the same
concentration gradient which caused the crossover from negative to positive.
Finally from five to ten percent NaCl there is an increase of 0.00067, from these results we can see
there is a small increase in averages as the concentration increases. However when analysing the
sample size results there was the highest initial mass volume for the egg at 0.002267, 0.002167 ...
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Our independent variable is the mass of the egg after being submerged into a sodium chloride
solution. The egg began to increase in size due to the passing of the concentration gradients
equilibrium. This is displayed in the results table using the average results. As the results table 1.
And the graph above it shows, the hypothesis was proven correct with minor problems when
compared to results in table 2. This showed there was dramatic differences in the data collected and
this could be due to multiple factors. It was concluded that between two and five percent sodium
chloride in 100mL water that the egg and the concentration reached an equal zero concentration
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37.
38. Is The Three To-One Blend Of Methylchloro Isothiazolinone
CMIT/MIT: The three–to–one blend of methylchloro–isothiazolinone (CMIT) and
methylisothiazolinone (MIT) is commonly used as a biocide in polymer dispersions. CMIT/MIT is a
broad–spectrum biocide that works between 3–9 pH. The mode of action for the CMIT/MIT is that
it reacts with the cell proteins causing the inhibition of respiration and ATP synthesis (PCIMAG).
Isothiazolones first mechanism which is performed in minutes is the swift inhibition of growth and
metabolism. This is then tailed by loss of viability due to irreversible cell damage which happens in
a matter of hours. Inhibition occurs by disrupting the metabolic pathways involving dehydrogenase
enzymes. Microbes are quickly inhibited due to the inhibition of critical physiological functions
including growth, respiration, and energy generation (adenosine triphosphate synthesis). Cell death
results in the destruction of protein thiols and production of free radicals. Compounds such as
surfactants can enhance and speed up the rate of inhibition and death. (Williams, 2007)
The interaction of isothiazolone biocides with microbial cells proceeds via several sequential
reactions. Initially, a biocide molecule reacts with a thiol group to form a disulphide linkage with the
biocide. This structure then interacts with a second thiol group to establish a new disulphide linkage.
Following this, the cell releases the biocide as a mercaptoacrylamide. The mercaptoacrylamide
derivative of CMIT tautomerizes to a thioacyl chloride under physiological conditions. The thioacyl
chloride is highly reactive and proceeds to interact with other cell macromolecules. The ability of
CMIT to degrade to a thioacyl chloride might account for it's much greater antimicrobial activity
when compared to BIT or MIT. (Daniel, 1997)
Barman did a study on the first–order rate constant and half–life values for the degradation of MIT
(Kathon 886 MW) and a MIT/CMIT (Kathon MWC) Mixture. These consist of 2–methyl–4–
isothiazolin–3–one and its chlorinated counterpart, 5–chloro–2–methyl–4–isothiazolin–3–one. At
100–fold more effective, the chlorinated counterpart is considered to be the active and require
concentrations 100–fold less than MIT. In fact, at very low concentrations of just 2–20 ppm
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39.
40. Chemistry : The Effects Of Chemical Reacting, And Its Effects
Chemical weathering occurs when a rock or building material is eroded and/or disintegrated by a
chemical process. This will occur primarily when a water is mixed with a chemical. Chemical
weathering will also often occur by water and in areas where warmer water or temperatures more
frequently occur and are common (kidsgeo), as the process accelerates and thrives in these
conditions. Often this process will occur in warmer seasons in the summer or spring to take
advantage of the warmer weather in order to accelerate the process. There are three distinct types of
chemical weathering that can occur: oxidation, hydrolysis, and carbonation. Oxidation will occur
when a molecule will gain an extra oxygen molecule. A good example of this is rust (passel), which
occurs when iron reacts with oxygen and it becomes iron oxide. So when a rock goes oxidised is
becomes weaker and can break down easily as the extra oxygen has weakened its structure .
Hydrolysis will occur when an extra water molecule is added. And carbonation will occur when
water reacts with carbon dioxide to form a carbonic acid, which can hollow out rocks by breaking
them down, leading to cave formations.
Purpose: The purpose of this lab is to demonstrate the effects of chemical weathering on zinc.
Hypothesis
If metal is placed in mixture of acid and water then the amount of rust will increase because the
metal will be more exposed to the acid for a period of time with one or the other mixture
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41.
42. The Chemistry Of A Heating Bath
A heating bath is used in the laboratory to allow the chemical reaction to occur at an elevated
temperature around 1000C. The beaker is a glass vessel which contains the chemical solutions for
the purpose of coating. It is placed in the electroless bath where the chemicals are being heated up.
The glass rod is used to stir the chemical where the magnetic stirrer is not necessary. The tongs are
used to lift the bath after the coating is completed. Tri–sodium citrate and thallium acetate are the
chemicals used during coating process which acts as a stabilizer for the bath. It stabilizes the
reaction occurring in the bath. Laboratory grade distilled water is used for the cleaning process and
also to mix up with the chemicals. Nickel chloride acts as the source for the coating process as the
nickel is being coated upon the surface of the substrate. Ethylene di amine is used as a complexing
agent which creates a bond between the nickel and aluminium and causes the coating. Thallium
acetate is used as the stabilizer. Sodium borohydride is the reducing agent which removes the
hydrogen ions which are being formed up inside the bath during the coating process. Fig.1 Zincate
pre–treatment process Table.1 Composition of Zincate Sodium hydroxide 400 g/l Zinc sulphate 120
g/l Sodium potassium tartarate 6 g/l Temperature Room Temperature Immersion time 3 mins Table.2
Nickel phosphorous and Nickel boron composition and conditions S.No Chemicals Used &
Conditions
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43.
44. What is Fermentation? Essay
Introduction:
Fermentation a metabolic process with occurs in the absence of oxygen molecules also known as an
anabolic reaction. It is a process of glycolysis in which sugar molecules are used to create ATP.
Fermentation has many forms the two most known examples are lactic acid and alcoholic
fermentation (Cressy). Lactic acid fermentation is used in many ranges from food production such
as bacteria to its use by fatigued muscles in complex organisms (Cressy). When experimenting with
organisms such as yeast which was done in this experiment you follow the metabolic pathway of
Alcoholic fermentation (Sadava). Where the sugar molecules are broken down and become ethanol
(Sadava). But the end product of fermentation is the production of ... Show more content on
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Showing that an acidic medium will still allow for yeast to ferment with little to no change from a
neutral pH which is supposed to be the optimal condition. But I predict that there will be a
significant change in how yeast will react in different conditions.
Methods:
Collect to 2 large beakers both large beakers are to be filled with hot water (labtutor). Then obtain
seven conical tubes these will be used to collect the levels of gas, you will also need test tube a
stopper and a plastic tube (labtutor). You want to fill the conical tube to at least 50 ml of water
(Cressy). Take the four conical tubes filled with water and place two in each beaker, to do this you
must invert the tube and cover the release hole as to not lose any water (Cressy). Then place the
beakers with the tubes in the bath so they can be at the same temperature as the bath (Cressy). Next
mark all of your test tubes in number order to be sure which tube contains what concentrations and
pH (Cressy). Having mixed a solution to the specifications of 2.5 ml of glucose in all tubes, 3 ml of
yeast in 2 tubes of pH 5, 2 tubes of pH 9, and the single pH 7 tube, the remaining two tubes will
contain no yeast as they will be negative controls. Next add 2 ml of pH buffer 3 tubes will receive
pH of 5, three will receive a pH of 9 and a single tube of pH 7. Finally add pure water to make sure
all test tubes have 10 ml of solution. When making the solutions
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45.
46. The Use Of Ester Interchange Reactions During The...
PRODUCTION OF PET
We utilize the rapidity of ester–interchange reactions during the production process. The acid
(terephthalic acid) is converted to the dimethyl ester, which is further purified by distillation or
crystallization. This is then allowed to react with the glycol by ester interchange. The reaction
generally is a two–step reaction a. First, low MW polyester is made with excess of glycol to ensure
that the hydroxyl end groups are formed and then the temperature is raised and pressure is decreased
to facilitate condensation of these molecules by ester interchange simultaneously with the loss of
glycol. [7]
PET resins can be produced in two ways commercially. These two ways are by using one among
dimethyl terephthalate (DMT) or terephthalic acid (TPA) with Ethylene Glycol (EG). These
processes are generally known as the DMT Process and the TPA process. The intermediate bis–(2–
hydroxyethyl)–terephthalate monomer (BHET) is produced in both these processes. This is
accompanied by methanol when using DMT and water when using TPA. The BHET intermediate
formed is polymerized with heat and catalyst to produce PET resins. The older route is the DMT
process. [8]
Process using DMT [9]
It is a two–step process. The ratio of DMT to EG is generally 2:1. There is the possibility of using
either batch operation or continuous operations to produce PET using DMT. Some basic differences
between the batch operation and continuous operations:
In the continuous process the
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47.
48. The Game Of Soccer : The Atp / Pc System
1. Soccer is one of the most demanding of all sports. The game is played on one of the largest fields
of any sport, for the longest sustained time and with the least amount of breaks. Players in a soccer
team are in continuous activity as they compete for loose balls, move to encourage teammates,
rotate positions and run to make a space or test opponents. Running, jumping, sprinting movements
in relation with sudden changes of acceleration and route outweigh the play. The power of the game
ranges between low–level activities such as walking or jogging to ones of high intensity such as
sprinting . This is what is known as intermittent exercise. The rhythm of soccer is dynamic and
constantly changing, which is a characteristic that divides it from other endurance sports , this
suggests that in order for a midfielder to successfully endure for the entire 90 minutes all three
energy systems assist in different stages although the ATP/PC system is dominant.
The ATP/PC system, which lasts up to 10 seconds, is the body's initial source of fuel and is reliant
on its stores of ATP and CP and provides the required burst of energy without the presence of
oxygen for high intensity purposes. This burst of energy is due to separating of the chemical bonds
between the Phosphate and Creatine which releases additional energy that helps produce more ATP
so that we have it upon requirement for only a short period of time. This system is the most
dominant system because this system is
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49.
50. Chemical Coagulation vs Electrocoagulation for Groundwater...
Arsenic contamination in groundwater has become a major health problem for human being. There
are many treatment methods have been developed for arsenic removal. It is important to develop a
treatment method that is economical and accessible for people who live in rural areas and cannot
afford the expensive treatment methods. Due to its several advantages, such as low cost and
maintenance, electrocoagulation is one of the promising methods that can be used for arsenic
treatment. In this study, we compare chemical coagulation with electrocoagulation and try to show
the advantages of electrocoagulation over chemical coagulation. Three experimental studies have
been reviewed and based on the results of these studies it has been concluded that by determining
optimum parameters such as electrolysis time, initial arsenic concentration, current density,
electrode surface area, and pH value, electrocoagulation can be an effective treatment method for
arsenic removal from groundwater due to its low cost, eco–friendly and low maintenance.
Keywords: arsenic removal, groundwater, electrocoagulation, chemical coagulation
Arsenic Removal from Groundwater by Electrocoagulation
Water is the most essential necessity for human life. Can you imagine life without clean drinking
water supply? Due to increasing the population of the world, the clean water has become a huge
concern. Arsenic has been one of the important components in contamination of drinking water in
many regions
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51.
52. Application Of Edible Coating And Shelf Life Study Essay
Studies on various aspect and objectives related to the present research work were carried during the
year 2016 in Department of Food Technology, Guru Jambheshwar University of Science and
Technology Hisar, Haryana. This chapter deals with the experimental set up of various experiments
performed during the study. The experimental design and statistical analysis are also explained as
well.
3.1 Materials:
Shellac was provided by National Institute of Gum and Raisin, Ranchi. Chemicals were used in this
study was of analytical grade and best grapes was purchased from the local market of Hisar,
Haryana.
3.2 Methodology employed for application of edible coating and shelf life study:
3.2.1 Coating Solution Preparation and Application
Dewaxed shellac, oleic acid, morpholine and ammonia in predetermined quantities were dispersed
in 100ml distilled water as shown in Table 3.1. The Coating treatment performed named as S1, S2,
S3, S4, and S5. Oleic acid is used an emulsifier and antioxidant agent. The other component
morpholine as emulsifying agent and ammonia was used to dissolve shellac being insoluble in
water. Samples dipped in distilled water were used as Control.
The solution was heated with constant stirring on a heating mantle at 70⁰C for 6 minutes. Samples
were dipped in different concentration coating for 20sec and the excess coating was drained. The
coated samples were then kept for surface drying at room temp for 15mins. Dewaxed shellac:
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53.
54. Stomach Acid Lab Report
This experiment investigates the effect of stomach acid at different pH levels on the solubility of
metformin hydrochloride tablets. According to my results, the metformin hydrochloride tablets
dissolved at a faster rate in the simulated stomach acid with less alcohol, and therefore, more acidic.
This conclusion, proves the hypothesis stated above. As predicted, the simulated acid with less
traces of alcohol was a more suitable environment for the medicine to dissolve at a faster rate.
Consequently, the tablets took a longer time to dissolve in the acid with a greater concentration of
alcohol. In consideration of the uncertainties, the two graphs above show that as the pH level
increases and becomes more basic, the amount of time for the tablets ... Show more content on
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When measuring out the substances for this experiment, an individual could get random errors when
slightly different values are collected each time they perform the measurement. Systematic errors,
on the other hand, are more difficult to detect but can be avoided if an individual looks for them
with care. A systematic error can occur in this experiment if the chemicals that are used are expired
or when the scales that are being used have been tampered with beforehand. Aside from random and
systematic errors, there are a few limitations in the design of this experiment. The use of small
graduated cylinders can provide inaccurate results for the experiment. Since the smaller cylinders
can only hold a small amount of acid, there is a possibility that the solutions can undergo
supersaturation, when a solution contains more of the dissolved material than could be dissolved by
the solvent. In a case that this happens, it would be difficult to predict when the tablet stop
dissolving in the solution. Therefore, due to the number of errors that could be made in this
experiment, the results are a little unreliable unless changes are made during the procedure and
design of the lab set
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55.
56. Essay about Module 1 Homework
Module 01 Homework Assignment Use the information presented in this module along with
additional outside research to answer the questions: 1. Describe how applied microbiology is used to
improve aspects of life and the environment. Microbiology is the study of microorganisms
(VanMeter, VanMeter, & Hubert, n.d., p.3). These are all of the things not visible to the human eye.
With the study of microbiology, it enables us to find things such as viruses and bacteria. This is
helpful because sickness and certain outbreaks can be prevented. In turn, this creates a safer more
stable environment. 2. Describe how the table of elements is ordered and discuss four common
elements in living organisms. Elements are ordered on the ... Show more content on Helpwriting.net
...
OSHA created a biosafety program. This provides rules and guidelines for handling and storing
chemicals in the laboratory. The program contains everything you need to be safe in the lab. It also
lays out an exposure plan in case someone were to get something in the lab. (VanMeter, VanMeter,
& Hubert, n.d., p.101). 6. Discuss the technique and importance of proper hand washing and
describe at least two other types of hand cleaning/sanitizing techniques. Hands should be washed
with soap and warm running water. The should also be washed for 20 seconds paying special
attention to the back of the hand, the wrist, between the fingers and under the nail. Rinse well and
dry with a single use towel. Always turn the water off with the towel. Aint–bacterial hand sanitizer is
also effective. Alcohol can also be used. (VanMeter, VanMeter, & Hubert, n.d., p.100–101). 7. Name
five pieces of information provided by the NIOSH Pocket guide to Chemical Hazards found at
www.cdc.gov. 1.Water flush immed | If this chemical contacts the skin, immediately flush the
contaminated skin with water. If this chemical penetrates the clothing, immediately remove the
clothing and flush the skin with water. Get medical attention promptly. | 2.Water flush prompt | If
this chemical contacts the skin, flush the contaminated skin with water promptly. If this chemical
penetrates the clothing, immediately remove the clothing and flush the skin with water
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57.
58. Classifying chemical reaction
02/19/14 Classifying Chemical Reactions Introduction Pre–lab questions 1. Which reactants used in
this experiment are flammable? Discuss the safety precautions that are necessary when working
with flammable materials in the lab? 2. Summarize the following description of a chemical reaction
in the form of a balanced chemical equation? 3. Common observations of a chemical reaction are
described in the introduction section. For each observation, name a common or everyday occurrence
that must involve a chemical reaction? Research question What is the appearance of reactant,
Evidence of chemical reaction, and properties of a product? Background information The
experiment is to observe a variety of chemical reactions and to identify patterns in ... Show more
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2. When the magnesium ignited, removed it from the flame and held it over an evaporating dish or a
pyrex watch glass until the metal had burned completely. Let the product fall into the evaporating
dish. 3. Turned off the laboratory burner and observed the properties of the product in the
evaporating dish. 4. Recorded observation in the data table Reaction 2 – 1.Used a Beral– type pipet,
added about 2mL (40 Drops) of 1M hydrochloric acid solution to a small test tube. 2. Obtained a 2–
3 cm strip of magnesium metal ribbon and coiled it loosely into a small ball. Added the magnesium
metal to the acid in the test tube. 3. Carefully felt the sides of the test tube and observed the resulted
chemical reaction for about 30 seconds. 4. While the reaction was still occurred, lighted a wood
splint and quickly placed the burned splint in the mouth of the test tube. Do not put the burned splint
into the acid solution. 5. Recorded observations in the data table. Reaction 3– 1. Obtained a clean
and dry test tube and placed a small amount ( about the size of a jelly bean) of ammonium carbonate
into the test tube. 2. Used a test tube clamp to held the test tube and gently heated the tube in a
laboratory burner flame for about 30 seconds. 3. Removed the test tube from the flame and places a
piece of moistened litmus paper in the mouth of the test tube. Identified any odor that is readily
apparent by wafted the fumes toward your nose. Caution: Do not sniff
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59.
60. Enzyme Catalase Experiment
Introduction:
Within a cell, enzymes are used as a catalyst to increase the rate of chemical reaction. They do not
consume themselves, rather they help in increasing the rate of reaction. Within the body, enzymes
vary depending on their specific functions. For instance, hydrogen peroxide is a toxic chemical, but
it breaks down into harmless oxygen and water. This reaction can be sped up using the enzyme
catalyst produced by yeast. Hydrogen peroxide is produced as a byproduct in cellular reaction,
because it is poisonous and must be broken down, therefore this reaction is important. The speeding
up of the reaction is shown below:
2H2O (aq) catalyses 2H2O (l) + O2 (g)
This experiment is designed to analyze how the enzyme catalase activity is affected by the pH
levels. The experiment has also been designed to outline all of the directions and the ways by which
the observation can be made clearly and accurately. Yeast, will be used as the enzyme and hydrogen
peroxide will be used as a substrate. This experiment will be used to determine the effects of the
concentration of the hydrogen peroxide versus the rate of reaction of the enzyme catalase.
Hypothesis:
The presence of catalyst will cause hydrogen peroxide to break down into water and oxygen. The
increase in the pH of the substrate will cause the increase in the rate of reaction. It will optimize at
pH 7 and will diminish/moderate after pH 9.
The important questions that will help clarify the
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61.
62. Ph Levels Lab Report Essay
The relatively close pH levels of Tap Water, Spring Water,
Flavored Water, and Seltzer Water.
Introduction
This experiment was performed to investigate the following hypothesis: The following four different
types of drinking water (spring water, seltzer water, tap water, and flavored water) we test will
relatively have the same pH level.
Our group decided to test different types of drinking water to see if a pH level of tap water is
comparable to other types of water. Many people believe that city water has many chemicals,
causing us to form the expirement to see how close the different types of drinking water's pH levels
are.
Materials and Methods
For the first part of our exiperiment we used the Red Cabbage Indicator. Red ... Show more content
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We then moved the electrode in one of the beakers of water we wanted to test. We measured the pH
level, recorded it, then placed it back into the clean water it was orignally in. We repeated these
steps for each of the different type of drinking water.
The control treatment in our expirement was thr red cabbage indicator. The dependent variable is the
pH of the water. The independent variable is the different types of drinking water ( tap water, spring
water, seltzer water, and flavored water). The standard variables in the expirement are the clean test
tubes, the clean pipettes, the Paraflim, the pH tester, and the pH levels pH 2, pH 4, pH 6, pH 7, pH
8, pH 10, and pH 12.
Results
Table 1 shows the standard of the standard of the expirement. It is used to compare the color of the
red cabbage expirement to form an educated guess on the pH level of the different types of water.
Table 2 shows the pH numbers we got from the red cabbage expirement and from the pH tester. This
informations enables to compare the red cabbage and the pH tester numbers in order to prove the red
cabbages accuaracy, and to prove our hypothesis that all of the pH numbers of the different types of
drinking water are relatively close.
Table 1: Red Cabbage Indicator standards pH LEVEL | COLOR | 2 | Red | 4 | Pink | 6 | Purple | 7 |
Dark Purple | 8 | Blue | 10 | Dark Green | 12 | Green |
Table 2: Table of red
65. Chemical Reactions
Chemistry
"Chemical Reaction and the PH Scale" Chemical reactions are the heart of chemistry. People have
always known that they exist. The Ancient Greeks were the firsts to speculate on the composition of
matter. They thought that it was possible that individual particles made up matter. As you might
imagine, it's useful to be able to measure the acidity of solutions. Scientists have come up with the
pH scale for determining the concentration of acid in a solution so we can distinguish between
solutions with varying acidity. A Chemical reaction is the outcome of two or more elements together
results in the formation of a chemical bond between atoms and compound. Chemicals react together
due to ... Show more content on Helpwriting.net ...
The PH Scale which is a diagram that is used to show the different measurements of water. In
general is important to know how the pH scale works because it determines whether or not a liquid
is acidic or
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66.
67. Conventional Drug Delivery Systems ( Ddss )
Abstract:
With the emergence of more novel and effective drug therapies, increased importance is being
placed upon the methods by which these drugs are being delivered to the body. Different
methodologies have been heavily investigated as possible solutions , one of these methods are
intelligent or 'Smart polymeric drug–delivery systems'. "Stimuli responsive" and "self regulating"
drug delivery systems have captured the imagination of researchers, in large part because they
suggest a means to mimic the physiological homeostatic feedback mechanisms that are essential for
health. As dysregulation of homeostasis is a feature of many diseases such as diabetes and cancer.
1. Introduction:
Conventional drug delivery systems (DDSs) are often accompanied by systemic side effects that
mainly are attributed to their nonspecific bio–distribution and uncontrollable drug release
characteristics. To overcome these limitations, advanced controlled DDSs have been developed to
achieve the release of payloads at the target sites in a spatial controlled manner.
Commercially available controlled release devices offer several advantages, e.g. they maintain the
drug within the desired therapeutic range with just a single dose, they allow localized drug delivery
which ultimately may reduce the need for follow–up care, they preserve drugs that are rapidly
destroyed by the body and ultimately improve patient compliance.
With the breakthrough of the biotechnology field in medicine, many advantages of
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68.
69. Is Soda Really Bad?
Is soda really that bad? Time and time again magazines, schools, and television say that sodas are
harmful to the body. They go on to scare people to death, by saying that sodas have been linked to
obesity. They state that the rising consumption of sugary drinks has been a major contributor to the
obesity epidemic (Harvard). They also say, that it is related to kidney damage and cancer (Boyles).
In reality, these sodas are not as bad as they have been made out to be, as long as they are drunk in
moderation. Drinking one soda will not kill people, soda is not the enemy! As a matter of fact, sodas
have a great benefit to everyone who drinks them, from curing multiple stomach issues, giving
people that extra boost to get you through the day, to using it as a multi–purpose household cleaner.
Come and join the millions of soda drinkers and enjoy the pleasing taste and big benefits found is
this small can. Soda drinkers hear a soda can being opened and it is like music to their ears. They
hear the fuzziness and bubbles inside the can and their mouth begins to tingle eagerly waiting to
take that sip. As they taste that sip of sweetness inside their mouth, their taste buds are jumping for
joy as their thirst is being quenched. As the soda goes down their throat, it is getting deeper into
their body and their body is thanking them for the wonderful benefits they are about to experience.
First of all, when someone has an upset stomach where do people turn to? Well, it would be a
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70.
71. Taking a Look at Polyester Fiber
2.2 Polyester Fiber
2.2.1 Background and General Properties of Polyester Fiber
Polyesters are those fibers containing at least 85% of a polymeric ester of a substituted aromatic
carboxylic acid including but not restricted to terephthalic acid and f–hydroxybenzoic acid. The
major polyester in the market is polyethylene terephthalate (PET), an ester formed by step growth
polymerization of terephthalic acid and the diol ethylene glycol. The polyester fibers all have similar
properties, are highly resilient and resistant to wrinkling, possess high durabilily and dimensional
stability, and are resistant to chemical and environmental attack(Needles, 1986). In 1996, 24.1
million metric tons of manmade fibres were produced globally. The main volume gain took place in
production of PET fibres (PET filament 9%, PET staple 4%) (Froehlich, 1997). Dramatic growth in
PET fibre production is foreseen in Asia in the near future (Harris, 1996). The cost of polyester, with
the combination of its superior strength and resilience, is lower than that of rayon. Polyester fibres
are hydrophobic which is suitable for lightweight facing fabrics used in disposable industry
providing a perceptible dry feel on the facing, even when the inner absorbent media is fully
saturated. As the new methods of PET processing and bonding of are developed, rayon is replaced
by polyester on the market. 49% of the total nonwovens market share in USA belongs to polyester
staple, reaching up to 291 million pounds in
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72.
73. The Dangerous Everyday
There are things all around us that can be very dangerous and we might never know. Soaps and
detergents are one of those things. Acids and bases are everywhere but, there are two specific types:
Sulphuric Acid and Sodium Hydroxide which we use on a regular day bases. An acid classifies a
wide range of materials including Sulphuric acid and bases Sodium Hydroxide. When
manufacturing soaps they use Sodium Hydroxide, and detergents use Sulphuric Acid. But these two
can be very poisonous, and there are many symptoms that may happen, some even severe. The title
shows how much people may be using dangerous things without having the knowledge that they can
harm them.
Acid and bases can be found in our everyday lives. An acid is a compound that usually has a sour
taste, containing hydrogen that can be replaced by a metal to form salt. Bases taste bitter and feel
slippery, their water solution conducts and electric currents. When acids and bases are put together
they make salt and water. The Arrhenius theory states that acids are substances which produce
hydrogen ions in a solution and bases are substances in which produce hydroxide ions in a solution.
Neutralization happens when hydrogen ions and hydroxide ions produce water. Something we use
every is soaps, detergents and fertilizers, all of these have acids and bases. The manufacturing of
soaps use the base Sodium hydroxide and the detergent and fertilizer use Sulphuric acid. Sodium
hydroxide is a white solid,
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74.
75. Investigating The Relationship Between Ph And Water Hardness
The purpose of this investigation was to determine the relationship between pH and water hardness.
Water samples from above the Mount Morgan mine site and below the Mount Morgan mine site
were also compared.
8.1 Analysis of the Data
It was hypothesised that the water sample from above the mine site would be of better water quality
than the sample from below the mine site. It was found that this was, in fact, the case. As seen in
Table 7.2, the above sample had lower acidity, hardness and conductivity than the below sample.
Given that acidity is indicated by a pH of below 7, the below mine water sample was considered
acidic, at a pH of 4.92. Conversely, the above mine site sample had a pH of 7.35, indicating an
almost neutral profile.
The above mine sample had a conductivity of 2200 µS/cm, whereas the below mine sample had a
conductivity of 7500 µS/cm. This suggests that there are a significantly greater number of ions in
solution in below mine water than above mine water.
The below mine sample also had greater water hardness, with a calcium ion concentration of
5183.29 mg/L, compared with the above mine sample's hardness of only 115.02 mg/L.
The above mine water mostly exhibited water quality parameter values that aligned with the water
quality guidelines for fresh water. With an almost neutral pH of 7.35, meaning it is within the
recommended pH range of 6.8–9.5 and is also safe for consumption. The hardness (concentration of
calcium ions) of 115.02 mg/L also lies
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76.
77. Part a: Dehydration of 1-Butanol & 2-Butanol/Part B:...
Ashley Droddy
CHM 235LL–Monday, 3/19/2012 & 3/26/2012
Part A: Dehydration of 1–butanol & 2–Butanol/Part B: Dehydrobromination of 1–Bromobutane
& 2–Bromobutane
Abstract
The objective of this experiment is to successfully perform a dehydration of 1–butanol and 2–
butanol, also dehydrobromination of 1–bromobutane and 2–bromobutane to form the alkene
products 1–butene, trans–2–butene, and cis–2–butene. The dehydration reactions react under and
acid–catalysis which follows an E1 mechanism. It was found that dehydration of 1–butanol yielded
3.84% cis–2–butene, 81.83% trans–2–butene, and 14.33% 1–butene, while 2–butanol is unknown
due to mechanical issues with the GC machine. For the dehydrobromination, with the addition of a
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That the more stable alkene trans–2–butene, is the major product at approximately 82%. While, the
two minor products would be 1–butene at 14%, and cis–2–butene at only approximately 4%.
Although, dehydration was not performed on 2–butanol, it would also produce the 3 isomeric
alkenes like 1–butanol via an E2 mechanism. The percentages would probably be very similar as
well. With trans–2–butene, being the major product, and cis–2–butene and 1–butene being minor
products as well. The GC results would appear again very similar to 1–butanol with 3 peaks
representing the 3 alkenes produced, however, 2–butanol has a lower BP, so it takes longer to react
and produce gaseous mixture because it is a secondary alcohol.
Part B: Dehydrobromination of 1–bromobutane & 2–bromobutane Compound | Temperature
(⁰C) | Products | Peak Area(mm2) | % Composition | 1–bromobutane | 90 | Trans–2–butene | ––––– |
–––– | | | Cis–2–butene | ––––– | –––– | | | 1–butene | 17500 | 100 | 2–bromobutane | 80 | Trans–2–
butene | 2469 | 49.95 | | | Cis–2–butene | 3336 | 13.09 | | | 1–butene | 8741 | 36.97 |
–(GC) Calculations for relative amount of products:
1–bromobutane:
Total peak area=17500 mm2
17500 mm2/17500 mm2x100%=100%, 1–butene
2–Bromobutane:
Total peak area=6679mm2
2469 mm2/6679 mm2x100%=36.97%, 1–butene
3336 mm2/6679 mm2x100%–=49.95% trans–2–butene
78. 8741 mm2/6679 mm2x100%=13.09% cis–2–butene
1–bromobutane with a strong base reacts
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79.
80. Chemistry lab report Essay
The goal of the project was to characterize an "unknown" organic acid in order to make a proper
identification of the acid, while learning proper techniques for scientific measurement and analysis
of error.
In order to ensure the most accurate data, a purification was performed by the process of
recrystallization. To perform the recrystallization the powder was dissolved in a minimal amount of
hot ethanol/H2O solvent that allowed the unknown powder to crystallize properly when cooled. This
process allowed for the removal of soluble impurities when suction filtered. A sample of the
unknown acid was weighed at 8.24 g, and it was found that 164ml of a 40% ethanol, 60% H20
solvent dissolved the 8.24 g of unknown acid when heated. The ... Show more content on
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Phenolphthalein was used as an endpoint indicator to determine the molarity of the NaOH solution,
which was found to be approximately .0979 M. The data collected from the titration follows in the
table below.
"NaOH Titration"
Trial I II III
Mass KHP (g) .403 .402 .411
Final NaOH 21.02mL 41.04mL 30.01mL
Initial NaOH .89mL 21.02mL 9.50mL
Volume NaOH Total 20.13mL 20.02mL 20.60mL
Molarity NaOH .0980 M .0980 M .0977 M
The molarity of each trial was found using the formula below; following the formula is a sample
calculation:
Molarity of NaOH Solution = Mass KHP (g) / [(204.34 g/mole) x (Delivered NaOH (ml)]
.403g /[(204.24g/mole)x(0.02013L)] = .0980 moles/liter
81. To ensure the best possible data, the error of the collected data was determined. This error was found
to be: (9.80–9.77)/9.77 = .003 x 100% = .31% error.
The equivalent weight of the unknown was determined by titration with NaOH. By discovering the
amount of NaOH required to react with the unknown acid, it was possible to determine the
equivalent weight of 98.4 g/mole. Three samples of the pure unknown acid were weighed at .403g,
.406g, and .394g. Each sample was placed in a flask and dissolved in approximately 40–50mL of the
heated solvent used in the recrystallization (40% ethanol/60% H2O). A drop of Phenolphthalein was
added to each flask. Each flask was titrated with the standardized
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