1) This experiment aimed to determine the statistical errors associated with diluting a 10M NaOH solution to 0.05M using seven different dilution pathways, including both direct and serial dilutions.
2) The results showed that all dilution pathways produced solutions with concentrations between 0.024M to 0.031M, indicating errors of 0.02-0.03 compared to the theoretical concentration of 0.05M. The serial dilution pathways had higher errors than the direct dilution.
3) Sources of error included inaccuracies in measuring and transferring small volumes, inefficiencies in mixing during serial dilutions, and analyte absorption to container surfaces during transfers. The highest number of dilution steps corresponded to the largest
I hope You all like it. I hope It is very beneficial for you all. I really thought that you all get enough knowledge from this presentation. This presentation is about materials and their classifications. After you read this presentation you knowledge is not as before.
This document describes procedures for preparing various chemical solutions. It details how to make 3M nitric acid, 1.5M sulfuric acid, 0.5N phosphoric acid by dilution, and 5% and 25% sodium hydroxide solutions by dissolution. The key steps, materials, and dilution/dissolution formulas are provided. Safety tips are also listed at the end regarding handling chemicals and labeling prepared solutions.
The document reports on an experiment to determine the enthalpy change of the neutralization reaction between sodium hydroxide and hydrochloric acid. 150 mL of 1M HCl and 50 mL of 1M NaOH were mixed in a polystyrene cup calorimeter. The temperature increase of 0.75°C was used to calculate the energy transferred of 156.75 J. Thermochemistry principles are discussed including definition of enthalpy change, methods to determine it including calorimetry, and equations used to calculate energy from temperature change measurements in solution calorimetry.
The document discusses colloids and their classification. It defines colloids as substances that are microscopically dispersed through another substance, with particle sizes between 10-10000 Angstroms. Colloids are classified in several ways, including by particle size (molecular dispersion, colloidal dispersion, coarse dispersion), physical state of phases, type of dispersed particles (multimolecular, macromolecular), appearance (sols, gels), and electrical charge on particles (positive, negative). Common colloidal systems include sols, emulsions, foams and aerosols. Micelle formation in colloids and the critical micelle concentration are also explained.
1. The document describes an experiment to determine the protein concentration of various egg samples using the Biuret and Lowry assays.
2. The Biuret assay found that chicken egg had the highest protein concentration at 20 mg/mL, while duck egg had the lowest at 10 mg/mL.
3. The Lowry assay found that duck egg had the highest protein concentration at 5.6 mg/mL, while chicken egg had the lowest at 1.6 mg/mL.
I hope You all like it. I hope It is very beneficial for you all. I really thought that you all get enough knowledge from this presentation. This presentation is about materials and their classifications. After you read this presentation you knowledge is not as before.
This document describes procedures for preparing various chemical solutions. It details how to make 3M nitric acid, 1.5M sulfuric acid, 0.5N phosphoric acid by dilution, and 5% and 25% sodium hydroxide solutions by dissolution. The key steps, materials, and dilution/dissolution formulas are provided. Safety tips are also listed at the end regarding handling chemicals and labeling prepared solutions.
The document reports on an experiment to determine the enthalpy change of the neutralization reaction between sodium hydroxide and hydrochloric acid. 150 mL of 1M HCl and 50 mL of 1M NaOH were mixed in a polystyrene cup calorimeter. The temperature increase of 0.75°C was used to calculate the energy transferred of 156.75 J. Thermochemistry principles are discussed including definition of enthalpy change, methods to determine it including calorimetry, and equations used to calculate energy from temperature change measurements in solution calorimetry.
The document discusses colloids and their classification. It defines colloids as substances that are microscopically dispersed through another substance, with particle sizes between 10-10000 Angstroms. Colloids are classified in several ways, including by particle size (molecular dispersion, colloidal dispersion, coarse dispersion), physical state of phases, type of dispersed particles (multimolecular, macromolecular), appearance (sols, gels), and electrical charge on particles (positive, negative). Common colloidal systems include sols, emulsions, foams and aerosols. Micelle formation in colloids and the critical micelle concentration are also explained.
1. The document describes an experiment to determine the protein concentration of various egg samples using the Biuret and Lowry assays.
2. The Biuret assay found that chicken egg had the highest protein concentration at 20 mg/mL, while duck egg had the lowest at 10 mg/mL.
3. The Lowry assay found that duck egg had the highest protein concentration at 5.6 mg/mL, while chicken egg had the lowest at 1.6 mg/mL.
Saponification is the process of making soap, which involves a reaction between fats/oils and a strong alkali like sodium hydroxide. This produces soap and glycerol. Soap molecules have a polar, water-soluble end and a nonpolar, water-insoluble end, allowing them to suspend oil in water and lower surface tension to help cleanse surfaces. There are two main types of soap: those made from animal/plant fats through saponification, and synthetic soapless detergents made from chemical oils.
This document summarizes an experiment to test the vitamin C content of various fruit and vegetable juices. The experiment involves using an iodine solution to test for the presence of vitamin C in orange, pomegranate, lemon, carrot, celery, tomato, parsley, cherry, grapefruit and apple juices. The results show that lemon and grapefruit juices required the fewest drops of iodine solution, indicating the highest vitamin C content, while tomato juice required the most drops, indicating the lowest vitamin C content. In conclusion, the experiment demonstrates that while all the juices contain vitamin C, the amounts vary significantly between sources.
IB Chemistry HL IA Rate of reaction, Chemistry labAssia Chelaghma
The document describes an experiment to determine how different concentrations of hydrochloric acid affect the rate of reaction with copper (II) powder. A colorimeter will be used to measure the absorbance of light by solutions containing copper (II) and hydrochloric acid over three minutes. Five concentrations of hydrochloric acid will react with 20g of copper (II) powder in separate trials. Variables like temperature, volume, and light intensity will be controlled. Absorbance readings will be taken and used to calculate the order of reaction and compare how concentration impacts the rate. The experiment will be repeated three times for each concentration to collect sufficient data.
Activated Carbon For Distilling Purposes HandbookEdward Dobson
This document discusses activated carbon and its use in purifying alcohol. It describes activated carbon as a porous substance used to absorb impurities. There are three types of pores in activated carbon: micro pores, meso pores, and macro pores. The document explains that the effectiveness of activated carbon for purifying alcohol depends on the combination and distribution of these pore types, as different pore sizes absorb different impurities. It provides guidance on selecting the right activated carbon based on the pore structure.
The document summarizes the key stages of cellular respiration: glycolysis, the Krebs cycle, and the electron transport chain. Glycolysis breaks down glucose into pyruvate and occurs in the cytoplasm, producing a net of 2 ATP. The Krebs cycle further oxidizes pyruvate in the mitochondrial matrix, producing carbon dioxide, hydrogen ions, and more ATP. The cytochrome system uses hydrogen ions to power ATP synthesis via oxidative phosphorylation. Overall, 38 ATP are produced from each glucose molecule through these stages of aerobic respiration.
1. This document describes experiments to study the effect of pH on the rate of fermentation in yeast. Students will set up solutions with yeast in buffers of varying pH and measure the amount of carbon dioxide produced over time.
2. The results will be recorded and two graphs will be made: one showing gas production over time for each pH, the other showing gas produced at 40 minutes for each pH. This will help determine the effect of pH on the rate of fermentation.
3. The effect of pH and possible mechanisms will be discussed, drawing on cell biology and metabolic knowledge.
Berikut merupakan referensi penetapan dalam analisis kimia kuantitatif konvensional berdasarkan pengukuran berat ( Gravimetri ) sebagai bahan pertimbangan dalam laporan atau informasi .
Classic, mini chemistry experiments- some require materials typically found in a high school chemistry lab, while others are extremely simple. Very straightforward!
This document describes the process of acid-base titration to determine the concentration of an unknown solution. A titration involves using a solution of known concentration (the standard solution) to neutralize a precisely measured volume of the unknown solution. An indicator is used to detect the endpoint of the titration reaction. The concentrations and volumes are then used to calculate the concentration of the unknown solution. The document provides instructions for using titration to determine the concentration of sodium hydroxide and white vinegar solutions. Sodium hydroxide is standardized against a primary standard potassium hydrogen phthalate solution before being used to titrate the vinegar.
An acid-base titration involves using a solution of known concentration (the standard solution) to neutralize a precisely measured volume of an unknown solution. The titration endpoint is detected using an indicator that changes color at neutralization. The volumes and concentrations are then used to calculate the concentration of the unknown solution. This document describes how to use a standard NaOH solution to determine the concentration of vinegar through titration.
Chemistry Lab Report on standardization of acid and bases. Karanvir Sidhu
I hope it might be helpful to you.
Email me on sidhu.s.karanvir@gmail.com to see more work.
Follow me at Linkedln
https://www.linkedin.com/in/karanvir-sidhu-b6995864/
This document describes a procedure for determining the acidity of water samples. It involves titrating an aliquot of the water sample with a sodium hydroxide solution of a known normality until the color change endpoint is reached using either phenolphthalein or methyl orange indicators. The volume of sodium hydroxide used is then used to calculate the total or mineral acidity levels present in the water sample expressed as mg/L of calcium carbonate equivalent. Precise sample handling, chemical preparation steps, a data sheet format, and calculation equations are provided to standardize the acidity determination.
This document provides guidelines and procedures for testing packaged drinking water according to Indian standards. It discusses the required chemical tests to assess compliance with standards, including tests that must be conducted four hourly, daily, weekly, and monthly. The key tests covered include analyzing color, odor, taste, turbidity, pH, total dissolved solids, chloride, and various metals and anions. The standard methods and permissible limits specified by the Bureau of Indian Standards are provided for each test parameter. Precautions for safe laboratory work are also outlined.
1) The student conducted an experiment to determine the relationship between the mass of different antacid medicines (Rennie, Kompensan, Talcid) and the volume of hydrochloric acid needed for titration. Different masses of each medicine were reacted with hydrochloric acid and the volume required was measured.
2) The results were presented in tables showing the raw data and averages from multiple trials. As the mass of each medicine increased, the volume of hydrochloric acid needed for titration also increased.
3) Of the three medicines tested, Talcid required the greatest volume of hydrochloric acid on average, indicating it was the most effective at reducing acidity.
The document summarizes an experiment to measure the alkalinity of various water samples. Four samples were tested - tap water, bottled water, and two unknown solutions. Titration was performed using phenolphthalein and bromocresol green indicators to determine the phenolphthalein alkalinity and total alkalinity. The unknown samples had higher alkalinity levels than the tap and bottled water. Alkalinity is important to understand the buffering capacity of water and its ability to neutralize acids. The titration process and indicators help identify the presence of carbonate, bicarbonate, and hydroxide ions and determine the sample's alkalinity in mg/L CaCO3 units
The document describes an experiment to investigate the level of pollution in different water samples (P, Q, R and S) by measuring the time taken for methylene blue solution to decolorize in each sample. Water samples were collected from different sources and mixed with a methylene blue solution in labeled bottles. The bottles were observed over time to measure how long it took the solution to decolorize in each sample. It is hypothesized that sample P from an industrial area will be most polluted based on the shortest decolorization time. The results will show the relative level of pollution in each water sample.
This document describes an experiment to determine the acidity of a water sample. The experiment involves titrating the water sample with a standard sodium hydroxide (NaOH) solution using two different acid-base indicators - methyl orange and phenolphthalein. The titration with methyl orange determines the mineral acidity as mg/L of calcium carbonate (CaCO3), while titration with phenolphthalein determines the total acidity, including carbonic acid, as mg/L of CaCO3. The procedure, observations, and calculations for determining the mineral and total acidity are provided.
The document describes the Kjeldahl method for determining nitrogen content in organic and inorganic substances. It was developed in 1883 and involves three main steps: digestion using sulfuric acid to convert organic nitrogen to ammonium ions, distillation to separate ammonia from the digestion mixture, and titration to quantify the ammonia content. The Kjeldahl method is widely used to analyze samples like wastewater, soils, foods and fuels to determine their nitrogen, protein or nutrient content. While it remains the standard, it is not suitable for all types of nitrogen compounds and accuracy can be affected by factors like digestion time and non-protein nitrogen content.
The document describes an experiment that tests for four important organic functional groups - hydroxyl, carbonyl, carboxyl, and amino groups - using various chemical reagents. Tests are conducted on isopropyl alcohol, glycerol, ethylene glycol, salicylic acid, and urea to detect the presence of functional groups. A data sheet is included to record the results of the tests, which involve observing any color changes that occur upon addition of reagents like potassium dichromate, potassium permanganate, iron (III) chloride, silver nitrate, or sulfuric acid. Proper disposal procedures are outlined for the different waste mixtures produced.
Scanned with CamScanner1 STANDARIZATION OF A B.docxtodd331
This document provides instructions for a two-part experiment involving titration. In part A, students will standardize a NaOH solution by titrating it against a primary standard of KHP. In part B, students will use their standardized NaOH solution to determine the concentration of acetic acid in a vinegar sample through titration. Key steps and concepts discussed include buret usage, endpoint determination, stoichiometric calculations to determine concentration from titration data, and the purpose and characteristics of primary standards.
Saponification is the process of making soap, which involves a reaction between fats/oils and a strong alkali like sodium hydroxide. This produces soap and glycerol. Soap molecules have a polar, water-soluble end and a nonpolar, water-insoluble end, allowing them to suspend oil in water and lower surface tension to help cleanse surfaces. There are two main types of soap: those made from animal/plant fats through saponification, and synthetic soapless detergents made from chemical oils.
This document summarizes an experiment to test the vitamin C content of various fruit and vegetable juices. The experiment involves using an iodine solution to test for the presence of vitamin C in orange, pomegranate, lemon, carrot, celery, tomato, parsley, cherry, grapefruit and apple juices. The results show that lemon and grapefruit juices required the fewest drops of iodine solution, indicating the highest vitamin C content, while tomato juice required the most drops, indicating the lowest vitamin C content. In conclusion, the experiment demonstrates that while all the juices contain vitamin C, the amounts vary significantly between sources.
IB Chemistry HL IA Rate of reaction, Chemistry labAssia Chelaghma
The document describes an experiment to determine how different concentrations of hydrochloric acid affect the rate of reaction with copper (II) powder. A colorimeter will be used to measure the absorbance of light by solutions containing copper (II) and hydrochloric acid over three minutes. Five concentrations of hydrochloric acid will react with 20g of copper (II) powder in separate trials. Variables like temperature, volume, and light intensity will be controlled. Absorbance readings will be taken and used to calculate the order of reaction and compare how concentration impacts the rate. The experiment will be repeated three times for each concentration to collect sufficient data.
Activated Carbon For Distilling Purposes HandbookEdward Dobson
This document discusses activated carbon and its use in purifying alcohol. It describes activated carbon as a porous substance used to absorb impurities. There are three types of pores in activated carbon: micro pores, meso pores, and macro pores. The document explains that the effectiveness of activated carbon for purifying alcohol depends on the combination and distribution of these pore types, as different pore sizes absorb different impurities. It provides guidance on selecting the right activated carbon based on the pore structure.
The document summarizes the key stages of cellular respiration: glycolysis, the Krebs cycle, and the electron transport chain. Glycolysis breaks down glucose into pyruvate and occurs in the cytoplasm, producing a net of 2 ATP. The Krebs cycle further oxidizes pyruvate in the mitochondrial matrix, producing carbon dioxide, hydrogen ions, and more ATP. The cytochrome system uses hydrogen ions to power ATP synthesis via oxidative phosphorylation. Overall, 38 ATP are produced from each glucose molecule through these stages of aerobic respiration.
1. This document describes experiments to study the effect of pH on the rate of fermentation in yeast. Students will set up solutions with yeast in buffers of varying pH and measure the amount of carbon dioxide produced over time.
2. The results will be recorded and two graphs will be made: one showing gas production over time for each pH, the other showing gas produced at 40 minutes for each pH. This will help determine the effect of pH on the rate of fermentation.
3. The effect of pH and possible mechanisms will be discussed, drawing on cell biology and metabolic knowledge.
Berikut merupakan referensi penetapan dalam analisis kimia kuantitatif konvensional berdasarkan pengukuran berat ( Gravimetri ) sebagai bahan pertimbangan dalam laporan atau informasi .
Classic, mini chemistry experiments- some require materials typically found in a high school chemistry lab, while others are extremely simple. Very straightforward!
This document describes the process of acid-base titration to determine the concentration of an unknown solution. A titration involves using a solution of known concentration (the standard solution) to neutralize a precisely measured volume of the unknown solution. An indicator is used to detect the endpoint of the titration reaction. The concentrations and volumes are then used to calculate the concentration of the unknown solution. The document provides instructions for using titration to determine the concentration of sodium hydroxide and white vinegar solutions. Sodium hydroxide is standardized against a primary standard potassium hydrogen phthalate solution before being used to titrate the vinegar.
An acid-base titration involves using a solution of known concentration (the standard solution) to neutralize a precisely measured volume of an unknown solution. The titration endpoint is detected using an indicator that changes color at neutralization. The volumes and concentrations are then used to calculate the concentration of the unknown solution. This document describes how to use a standard NaOH solution to determine the concentration of vinegar through titration.
Chemistry Lab Report on standardization of acid and bases. Karanvir Sidhu
I hope it might be helpful to you.
Email me on sidhu.s.karanvir@gmail.com to see more work.
Follow me at Linkedln
https://www.linkedin.com/in/karanvir-sidhu-b6995864/
This document describes a procedure for determining the acidity of water samples. It involves titrating an aliquot of the water sample with a sodium hydroxide solution of a known normality until the color change endpoint is reached using either phenolphthalein or methyl orange indicators. The volume of sodium hydroxide used is then used to calculate the total or mineral acidity levels present in the water sample expressed as mg/L of calcium carbonate equivalent. Precise sample handling, chemical preparation steps, a data sheet format, and calculation equations are provided to standardize the acidity determination.
This document provides guidelines and procedures for testing packaged drinking water according to Indian standards. It discusses the required chemical tests to assess compliance with standards, including tests that must be conducted four hourly, daily, weekly, and monthly. The key tests covered include analyzing color, odor, taste, turbidity, pH, total dissolved solids, chloride, and various metals and anions. The standard methods and permissible limits specified by the Bureau of Indian Standards are provided for each test parameter. Precautions for safe laboratory work are also outlined.
1) The student conducted an experiment to determine the relationship between the mass of different antacid medicines (Rennie, Kompensan, Talcid) and the volume of hydrochloric acid needed for titration. Different masses of each medicine were reacted with hydrochloric acid and the volume required was measured.
2) The results were presented in tables showing the raw data and averages from multiple trials. As the mass of each medicine increased, the volume of hydrochloric acid needed for titration also increased.
3) Of the three medicines tested, Talcid required the greatest volume of hydrochloric acid on average, indicating it was the most effective at reducing acidity.
The document summarizes an experiment to measure the alkalinity of various water samples. Four samples were tested - tap water, bottled water, and two unknown solutions. Titration was performed using phenolphthalein and bromocresol green indicators to determine the phenolphthalein alkalinity and total alkalinity. The unknown samples had higher alkalinity levels than the tap and bottled water. Alkalinity is important to understand the buffering capacity of water and its ability to neutralize acids. The titration process and indicators help identify the presence of carbonate, bicarbonate, and hydroxide ions and determine the sample's alkalinity in mg/L CaCO3 units
The document describes an experiment to investigate the level of pollution in different water samples (P, Q, R and S) by measuring the time taken for methylene blue solution to decolorize in each sample. Water samples were collected from different sources and mixed with a methylene blue solution in labeled bottles. The bottles were observed over time to measure how long it took the solution to decolorize in each sample. It is hypothesized that sample P from an industrial area will be most polluted based on the shortest decolorization time. The results will show the relative level of pollution in each water sample.
This document describes an experiment to determine the acidity of a water sample. The experiment involves titrating the water sample with a standard sodium hydroxide (NaOH) solution using two different acid-base indicators - methyl orange and phenolphthalein. The titration with methyl orange determines the mineral acidity as mg/L of calcium carbonate (CaCO3), while titration with phenolphthalein determines the total acidity, including carbonic acid, as mg/L of CaCO3. The procedure, observations, and calculations for determining the mineral and total acidity are provided.
The document describes the Kjeldahl method for determining nitrogen content in organic and inorganic substances. It was developed in 1883 and involves three main steps: digestion using sulfuric acid to convert organic nitrogen to ammonium ions, distillation to separate ammonia from the digestion mixture, and titration to quantify the ammonia content. The Kjeldahl method is widely used to analyze samples like wastewater, soils, foods and fuels to determine their nitrogen, protein or nutrient content. While it remains the standard, it is not suitable for all types of nitrogen compounds and accuracy can be affected by factors like digestion time and non-protein nitrogen content.
The document describes an experiment that tests for four important organic functional groups - hydroxyl, carbonyl, carboxyl, and amino groups - using various chemical reagents. Tests are conducted on isopropyl alcohol, glycerol, ethylene glycol, salicylic acid, and urea to detect the presence of functional groups. A data sheet is included to record the results of the tests, which involve observing any color changes that occur upon addition of reagents like potassium dichromate, potassium permanganate, iron (III) chloride, silver nitrate, or sulfuric acid. Proper disposal procedures are outlined for the different waste mixtures produced.
Scanned with CamScanner1 STANDARIZATION OF A B.docxtodd331
This document provides instructions for a two-part experiment involving titration. In part A, students will standardize a NaOH solution by titrating it against a primary standard of KHP. In part B, students will use their standardized NaOH solution to determine the concentration of acetic acid in a vinegar sample through titration. Key steps and concepts discussed include buret usage, endpoint determination, stoichiometric calculations to determine concentration from titration data, and the purpose and characteristics of primary standards.
The document outlines procedures for determining various types of solids in water samples, including total solids, fixed solids, volatile solids, total dissolved solids, suspended solids, and settleable solids. Total solids include all materials retained after evaporation and drying of a sample. Fixed solids are the residues remaining after ignition, while volatile solids are lost during ignition. The procedures involve filtering samples, evaporating filtrates to determine dissolved fractions, and weighing residues to calculate concentrations.
This document provides procedures for conducting a 3-day biochemical oxygen demand (BOD3-27) test at 27°C. It describes the necessary apparatus, which includes BOD bottles and an incubator maintained at 27±1°C. Reagents include phosphate buffer solution, magnesium sulfate solution, calcium chloride solution, ferric chloride solution, acid and alkali solutions for pH adjustment, and a fresh glucose-glutamic acid solution used as a carbon source for microorganisms. The procedure involves filling BOD bottles with diluted sample and incubating for 3 days, then measuring the dissolved oxygen concentration to determine the amount of oxygen consumed by microorganisms.
1) The document is a chemistry project report submitted by Samuel Kumar about studying the digestion of starch by salivary amylase and the effect of temperature and pH on it.
2) Three experiments were conducted to study the digestion of starch by saliva, the effect of temperature on digestion, and the effect of pH on digestion.
3) The results showed that starch is digested by salivary amylase, higher temperatures increase the rate of digestion, and digestion does not occur under acidic or alkaline conditions.
This document provides guidance on calculations for molecular biology and biochemistry. It discusses:
- Using appropriate units like microliters and micromolar instead of liters and molar when working with small volumes and dilute solutions.
- Strategies for calculations including converting between concentration and number of moles and working with dilutions.
- How to use molecular weights to convert between molarity and weight per volume units.
- Considerations for calculations like anhydrous vs hydrated compounds and working with liquid densities.
- The role of buffers in maintaining pH for biological reactions.
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptxEduSkills OECD
Iván Bornacelly, Policy Analyst at the OECD Centre for Skills, OECD, presents at the webinar 'Tackling job market gaps with a skills-first approach' on 12 June 2024
Leveraging Generative AI to Drive Nonprofit InnovationTechSoup
In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
Philippine Edukasyong Pantahanan at Pangkabuhayan (EPP) CurriculumMJDuyan
(𝐓𝐋𝐄 𝟏𝟎𝟎) (𝐋𝐞𝐬𝐬𝐨𝐧 𝟏)-𝐏𝐫𝐞𝐥𝐢𝐦𝐬
𝐃𝐢𝐬𝐜𝐮𝐬𝐬 𝐭𝐡𝐞 𝐄𝐏𝐏 𝐂𝐮𝐫𝐫𝐢𝐜𝐮𝐥𝐮𝐦 𝐢𝐧 𝐭𝐡𝐞 𝐏𝐡𝐢𝐥𝐢𝐩𝐩𝐢𝐧𝐞𝐬:
- Understand the goals and objectives of the Edukasyong Pantahanan at Pangkabuhayan (EPP) curriculum, recognizing its importance in fostering practical life skills and values among students. Students will also be able to identify the key components and subjects covered, such as agriculture, home economics, industrial arts, and information and communication technology.
𝐄𝐱𝐩𝐥𝐚𝐢𝐧 𝐭𝐡𝐞 𝐍𝐚𝐭𝐮𝐫𝐞 𝐚𝐧𝐝 𝐒𝐜𝐨𝐩𝐞 𝐨𝐟 𝐚𝐧 𝐄𝐧𝐭𝐫𝐞𝐩𝐫𝐞𝐧𝐞𝐮𝐫:
-Define entrepreneurship, distinguishing it from general business activities by emphasizing its focus on innovation, risk-taking, and value creation. Students will describe the characteristics and traits of successful entrepreneurs, including their roles and responsibilities, and discuss the broader economic and social impacts of entrepreneurial activities on both local and global scales.
Gender and Mental Health - Counselling and Family Therapy Applications and In...PsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Communicating effectively and consistently with students can help them feel at ease during their learning experience and provide the instructor with a communication trail to track the course's progress. This workshop will take you through constructing an engaging course container to facilitate effective communication.
Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
Department of biochemistry cell ad molecular biology (1)
1. DEPARTMENT OF BIOCHEMISTRY, CELL AD MOLECULAR BIOLOGY
EXPERIMENT 1
STATISTICAL ERRORS IN DILUTIONS
GROUP 9
SAMUEL MENSAH BAFFOE 10623514
ADELAIDE OHUI FIERTI
NANA AMA KONADU -YIADOM
ALEXANDER DANQUAH
KUZAGBE KAFUI ESI
ERNEST ADJEI OKERTCHIRI
06/09/17
PRACTICAL PERIOD: TUES-1:30PM -4:30PM
UNIVERSITY OF GHANA-LEGON
2. INTRODUCTION
In our various homes, a cup of tea is enough to begin the day. In preparing this, you may unintentionally
increase the amount of sugar required. In order to reduce this sugar content, a volume of water is added to
the tea. This is a basic life principle that dates back to the advent of civilization. In science this process is
known as dilution.
Dilution is the process of reducing the concentration of solutes in a solution, usually simply by adding more
solvent to achieve the desired concentration. A number called the dilution factor is used to determine the
extent of the dilution in each dilution step. In a single dilution for example, suppose you must prepare a
diluted solution of 400ml disinfectant from the concentrated stock solution with water, a volume of 350ml of
water can be added to 50ml of the stock solution. The dilution factor is therefore 50ml/400ml which is 8.
To make a highly diluted solution, scientist employ a sequential dilution process known as serial dilution. In
serial dilution, the concentration of the stock solution decreases by same quantity in successive steps. Serial
dilution is mostly applied in microbiology, biochemistry and pharmacology. A microbiologist may decide to
dilute a bacterial culture in three step 1:100 serial dilution. In each step, he may add 990ml of water to 10ml
of the bacterial culture yielding dilution of 1:100, 1: 10000 and 1: 1000000 for the first, second and third
dilution steps respectively. The formula C1V1=C2V2 is used where C1 and C2 represents initial and final
concentrations while V1 and V2 are the initial and final volumes respectively.
In daily experiments conducted in the laboratory, errors are said to be inevitable. Some sources of errors
include; human errors of the experimenter, the instrumental errors of the measuring devices and the errors
associated with the method of analysis he employs. (Skoog & West, 1996).
According to Blobel (2005), statistical errors are due to statistical uncertainties; the difference between the
measured value and the expectation value. They are special kind of error in the class of random errors
(variation in repeated measurement taken).
This experiment is aimed at determining the errors in dilution of 10M NaOH to 0.05M using seven different
pathways.
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3. METHODOLOGY
DILUTIONS
A stock solution of 10M NaOH was diluted serially to 0.05M in seven different experimental pathways.
Experiment 1.
In a conical flask I, a 0.1ml of 10M NaOH was collected and diluted with 19.9ml of distilled water to 0.05M
making a total volume of 20ml. The 10ml pipette was used in this transfer.
Experiment 2
Distilled water of 5ml was added to 5ml of 10M NaOH to dilute it to 5M in test tube A. A volume of 0.1ml
of the 5M NaOH in test tube A was collected into conical flask II and diluted to 0.05M using 9.9ml of
distilled water. The 1ml and 10ml pipette was used in the transfer.
Experiment 3
Step 1 in experiment 2 was repeated. From the 5M NaOH obtained in test tube A was transferred 5ml into
test tube B and diluted to 2.5M using a 5ml of distilled water. A 5ml pipette was used in this transfer. A
volume of 0.2ml of 2.5M NaOH was collected into conical flask III and a 9.8ml of distilled water was added
to dilute it to 0.05M.
Experiment 4
Steps 1 and 2 in experiment 3 was repeated. In test tube C, a volume of 4ml of 2.5M NaOH from test tube B
was collected and diluted to 1.0M NaOH by adding 6ml of distilled water. In conical flask IV, 0.5ml of
1.0M NaOH was transferred and diluted to 0.05M with 9.5ml of distilled water.
Experiment 5
Steps 1, 2 and 3 in experiment 4 was repeated. A volume of 5ml of 1.0M NaOH in test tube C was delivered
into test tube D and a 5ml of distilled water was added to dilute it to 0.5M using the 5ml pipette. From this
0.5M NaOH, 1ml was transferred into conical flask V and diluted to 0.05M with 9ml of distilled water.
MATERIAL
10 NaOH, 0.05M HCL, phenolphthalein
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4. Experiment 6
Steps1, 2, 3 and 4 in experiment 5 was repeated. A 5ml pipette was used to transfer 5ml of 0.5M NaOH
from test tube D into test tube E and diluted to 0.25M with 5ml of distilled water. A 1ml pipette was used to
transfer 2ml of 0.25M NaOH into conical flask VI and this solution was diluted to 0.05M with 8ml of
distilled water.
Experiment 7
Steps 1, 2, 3, 4 and 5 in experiment 6 was repeated. From the resulting 0.25M NaOH was collected 4ml into
test tube F and diluted with 6ml of distilled water to 0.1M NaOH. A conical flask VII was used to collect
5ml of 0.1 NaOH and diluted to 0.05M using 5ml of distilled water.
All but experiment 1 was repeated to obtain a duplicate of the solutions of 10ml of 0.05M NaOH in the
conical flasks. In experiment 1, the 20ml of 0.05M NaOH diluted solution was divided into two.
TITRATION PROCEDURE
In each conical flask containing 10ml of NaOH solution, two drops of phenolphthalein was added changing
the colour of the NaOH from colorless to pink. The burette was filled with 0.05M HCl and titrated against
the 10ml of NaOH. Each titration was done two times and the titre values were recorded.
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5. RESULTS
TABLE 1. TITRE VALUES OF HCl FOR SEVEN EXPERIMENTAL PROCEDURES
TABLE 2. CALCULATED ERRORS IN DILUTION OF NaOH FROM 10M TO 0.05M
THEORETICAL VALUE OF CONCENTRATION (CT) =0.05M NaOH
Moles of Acid and Base at equivalent
point n= CV
CAVA=CBVB
CA = Concentration of HCl,
VA= volume of HCl used
CB = Concentration of NaOH ,
VB= volume of NaOH used
EXPERIMENTS TITRE VALUE
1
(ml)
TITRE VALUE
2
(ml)
AVERAGE
TITRE
(ml)
1 6.1 5.0 6.1
2 5.0 5.0 5.0
3 5.1 5.5 5.3
4 5.1 5.0 5.1
5 4.8 5.2 5.0
6 5.0 5.1 5.1
7 5.0 4.8 4.9
EXPERIMENTS
CONCENTRATION
OF NaOH FROM
TITRATION Cm
(M)
ERROR IN
DILUTION
CT-Cm
1 0.031≡0.03 0.02
2 0.027≡0.03 0.02
3 0.026≡0.03 0.02
4 0.025≡0.03 0.02
5 0.026≡0.03 0.02
6 0.026≡0.03 0.02
7 0.024 ≡ 0.02 0.03
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6. DISCUSSION
The titration of HCl against NaOH is a strong acid- base titration with mole ratio of 1:1.
NaOH (aq) + HCl (aq) NaCl (aq) + H2O (aq)
From the experimental results in table 2, it can be deduced that the concentration of the NaOH in experiment
3 that neutralized the acid had the least error (0.02) as calculated from the theoretical value of concentrated
of 0.05M. Experiment 7 recorded the maximum error of 0.03.
The two titre values recorded in experiment 1 differed from each other with a volume of 1.1ml. This value
exceeds in large extent the maximum expected difference of 0.2ml. The first titre value was used as the
average titre to compensate this error. Transfer inaccuracies during the dilution might have contributed to
the error in the two titre values. That is, in preparing two solutions of a 10ml NaOH, 20ml of the NaOH was
prepared from the stock solution of 0.1ml and this solution was divided into two separate conical flasks.
The final concentration of the NaOH solution in experiment 7 (0.024M) indicates the highest amount of
dilution from the stock solution of 10M.
The serial dilution process is faced with two major challenges: The first is error propagation across columns,
or rows. The second is the efficiency in mixing of samples (NaOH and distilled water) in the test tubes. Each
step in the serial dilution process leads to a less precise dispensing. (Gomes, Korbowski & Yates, 2017).
Comley (2007) argues that chemical substances adsorb the surfaces of the test tubes and the pipette tips used
to transfer the liquid. The concentration of the analyte then becomes far less than anticipated. (More
diluted).
It is observed that direct dilutions has some drawbacks in that small volumes of a stock solution of high
concentration is needed to dilute it to a very small concentration. The measurement of this small volumes are
done using micro pipettes and measuring equipment that measures very small quantities (<10-3 unit).
With the invention of the CyBio, pipetting of very small volumes is done easily. The CyBio® Diluspro is
used in serial dilutions while the CyBi®-Nanojest is applied in direct dilution of highly concentrated
solutions
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7. CONCLUSION
The aim of this experiment was successfully achieved. Statistical errors are associated with dilution
processes either serial or direct. The error associated with the serial dilution was maximum.
The highest dilution step used in this experiment was seven. Does increasing the number of steps increase
the extent of dilution?
REFERENCE
Blobel, V. (2005). Statistical error in Analysis. University of Hamberg.
Comley, J. (2007). Serial dilution vs direct dilution: Drug discovery Work Spring. Pg 36-50.
Gomez, M, Korbowski,J. & Yates, I. ( March 15, 2017). Assay: Accuracy and precision with serial Dilution.
Sample mixing efficiency with the BravoTM Liquid Handling Platform. Retrieved from genengnews.com-
articles/assay-accuracy-and-precision-with-serial-dilution/2038
Scoog, D.A & West, M.D (1969) Fundamentals of Analytical Chemistry, 2nd Ed. United State of America:
Holt, Rinehart and Winston Inc.
Statistical Errors (1997) Retrieved from teacher.nsrl.rochester.edu/phy.labs/statistics/statistics.htm
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