Chemistry is the study of matter and its composition, structure, properties, and reactions. It involves using the scientific method through observations, hypotheses, experiments, and theories. Measurements in chemistry use standardized metric units and scientific notation is used to write very large or small numbers in a condensed form.
Mediciones, Problemas de Conversión y Notación Científicafernandogc
This document provides information about scientific notation. It defines scientific notation as a way to write very large or very small numbers using a coefficient and power of 10. Examples are provided to show how numbers are written in scientific notation by moving the decimal point and representing the places moved as a power of 10. Common powers of 10 are listed. Learning checks are included to practice writing numbers in scientific notation and standard notation. The summary provides the key details about scientific notation in a concise manner.
This is a basic overview of your first chemistry exam. You will find real test problems and explanations so you know what to be expecting. We will also go over this presentation together.
1) The document provides an introduction to physics, outlining key concepts such as physical quantities, scalar and vector quantities, measurements, and errors in measurements.
2) It defines physics as the study of natural phenomena and properties of matter. Key topics in physics are then described, including mechanics, heat, waves, electronics, and atomic/nuclear physics.
3) The document distinguishes between scalar and vector quantities. Scalar quantities only require magnitude to be specified while vector quantities require both magnitude and direction.
4) Accurate measurements require selecting the appropriate instrument and accounting for errors such as parallax, zero error, and random error. Consistency in measurements is also important.
Chemistry is the study of matter and the changes it undergoes. Matter has mass and takes up space, and can be either elements or compounds. Elements are pure substances made of one type of atom, while compounds contain two or more elements chemically bonded together. Properties of matter include physical properties that can be observed without changing its composition, and chemical properties that involve its reactivity. Energy is the ability to do work or cause change and can exist in different forms like kinetic, potential, chemical, and heat energy. Heat is the transfer of energy between a system and its surroundings due to a temperature difference. The amount of heat required to change a substance's temperature can be calculated using the formula Q=mcΔT, where
This document provides instructions for homework assignments on scientific conversions and the scientific method. Students are asked to complete conversions between various units including feet to centimeters, grams to millimeters, Celsius to Kelvin, and Kelvin to Fahrenheit. They are also asked to calculate volume, pressure, and moles using given formulas and values. The document defines Avogadro's number as the number of molecules or atoms in a mole of substance, which is used to determine the number of moles from a given number of atoms.
This document provides examples for converting between metric measurement units using proportions. It includes examples converting centimeters to meters, kilograms to grams, milliliters to liters, meters to kilometers, grams to kilograms, grams to milligrams, and milliliters to liters. The document emphasizes using a proportion with the given measurement, given unit, unknown measurement, and unknown unit to perform the conversion. It also provides homework problems for students to practice additional conversions.
Lecture 3.2 through 3.4- Units, Conversions, & DensityMary Beth Smith
1 g/cm3 = 1000 kg/m3
So, 5.6 g/cm3 = 5.6 x 1000 kg/m3 = 5600 kg/m3
The correct answer is b.
3.3 Section Quiz
Convert 2.5 km to meters.
a) 2500 m
b) 0.0025 m
c) 2.5 m
d) 25,000 m
This document provides an overview of scientific measurement and units covered in a general chemistry course. It discusses the metric system of units used in science including the SI base units. It also covers scientific notation, significant figures, units of temperature, density, specific gravity, and heat measurement.
Mediciones, Problemas de Conversión y Notación Científicafernandogc
This document provides information about scientific notation. It defines scientific notation as a way to write very large or very small numbers using a coefficient and power of 10. Examples are provided to show how numbers are written in scientific notation by moving the decimal point and representing the places moved as a power of 10. Common powers of 10 are listed. Learning checks are included to practice writing numbers in scientific notation and standard notation. The summary provides the key details about scientific notation in a concise manner.
This is a basic overview of your first chemistry exam. You will find real test problems and explanations so you know what to be expecting. We will also go over this presentation together.
1) The document provides an introduction to physics, outlining key concepts such as physical quantities, scalar and vector quantities, measurements, and errors in measurements.
2) It defines physics as the study of natural phenomena and properties of matter. Key topics in physics are then described, including mechanics, heat, waves, electronics, and atomic/nuclear physics.
3) The document distinguishes between scalar and vector quantities. Scalar quantities only require magnitude to be specified while vector quantities require both magnitude and direction.
4) Accurate measurements require selecting the appropriate instrument and accounting for errors such as parallax, zero error, and random error. Consistency in measurements is also important.
Chemistry is the study of matter and the changes it undergoes. Matter has mass and takes up space, and can be either elements or compounds. Elements are pure substances made of one type of atom, while compounds contain two or more elements chemically bonded together. Properties of matter include physical properties that can be observed without changing its composition, and chemical properties that involve its reactivity. Energy is the ability to do work or cause change and can exist in different forms like kinetic, potential, chemical, and heat energy. Heat is the transfer of energy between a system and its surroundings due to a temperature difference. The amount of heat required to change a substance's temperature can be calculated using the formula Q=mcΔT, where
This document provides instructions for homework assignments on scientific conversions and the scientific method. Students are asked to complete conversions between various units including feet to centimeters, grams to millimeters, Celsius to Kelvin, and Kelvin to Fahrenheit. They are also asked to calculate volume, pressure, and moles using given formulas and values. The document defines Avogadro's number as the number of molecules or atoms in a mole of substance, which is used to determine the number of moles from a given number of atoms.
This document provides examples for converting between metric measurement units using proportions. It includes examples converting centimeters to meters, kilograms to grams, milliliters to liters, meters to kilometers, grams to kilograms, grams to milligrams, and milliliters to liters. The document emphasizes using a proportion with the given measurement, given unit, unknown measurement, and unknown unit to perform the conversion. It also provides homework problems for students to practice additional conversions.
Lecture 3.2 through 3.4- Units, Conversions, & DensityMary Beth Smith
1 g/cm3 = 1000 kg/m3
So, 5.6 g/cm3 = 5.6 x 1000 kg/m3 = 5600 kg/m3
The correct answer is b.
3.3 Section Quiz
Convert 2.5 km to meters.
a) 2500 m
b) 0.0025 m
c) 2.5 m
d) 25,000 m
This document provides an overview of scientific measurement and units covered in a general chemistry course. It discusses the metric system of units used in science including the SI base units. It also covers scientific notation, significant figures, units of temperature, density, specific gravity, and heat measurement.
The document provides an overview of fragrances chemistry and the perfume industry. It discusses:
- The history of perfumes and key ingredients like coumarin.
- How most luxury perfume brands outsource fragrance creation to large flavor and fragrance companies like Givaudan, Firmenich, and IFF.
- Techniques in fragrance chemistry like developing synthetic versions of rare and expensive natural ingredients to preserve resources and ensure sustainability and safety.
- The roles of different fragrance types (e.g. top notes, base notes) and molecules in constructing complex perfume accords and compositions.
The document summarizes key points about cooking methods and chemistry:
- It discusses two methods of tenderizing meat: hanging meat to age and using mechanical or chemical actions like beating or marinating.
- It explains how a pressure cooker works by raising the pressure above atmospheric pressure, increasing the boiling point of water and allowing food to cook faster while retaining more nutrients.
- It identifies starch and protein as major constituents in flour and describes how their structures are altered through processes like gelatinization and denaturation during cooking.
SOLID DISPERSION
Definition: The technology is the science of dispersing one or more active ingredients in an inert matrix in the solid stage.
Need of solid dispersion:
Increases Oral bioavailability of a drug
Increased dissolution rate.
Enhanced release of drugs from ointment.
Improved the solubility & stability.
The concept of solid dispersion was originally proposed by Sekiguchi & obi.
Increasing the dissolution, absorption & therapeutic efficacy of drugs in dosage forms.
Increasing solubility in water.
Improving the oral absorption and bioavailability of BCS Class II drugs.
The document discusses a study on enhancing the solubility of loratadine, a class II drug with low solubility and high permeability, through solid dispersion techniques. Loratadine's solubility decreases with increasing pH. The study prepares solid dispersions of loratadine with β-cyclodextrin, HPC, and PEG-6000 and finds their solubility is greatly improved, especially at higher pH levels. Solubility is tested in buffers from pH 1.2 to 7.4. The co-precipitation method provides better solubility results than physical mixing for the dispersions tested.
The document discusses solid dispersion and complexation techniques for improving the solubility and bioavailability of poorly soluble drugs. Solid dispersion involves combining a drug with a hydrophilic carrier to improve its dissolution rate. Types of solid dispersions include solid solutions, eutectic mixtures, and glass suspensions. Preparation techniques include hot melt, solvent evaporation, melt extrusion, and kneading. Complexation, such as drug-cyclodextrin inclusion complexes, enhances drug solubility and stability. These techniques are important for formulating oral drugs that are limited by poor solubility.
This document provides information about various chemicals and nutrients found in the kitchen. It discusses baking soda, vinegar, salt, citric acid, lye, bleach, water, and other common kitchen ingredients. It also covers macronutrients like carbohydrates, proteins, fats, and micronutrients like vitamins and minerals. Finally, it discusses starches and different types of cooking oils used in the kitchen.
Food Chemistry is the study of chemical processes and interactions of all biological and non- biological components of foods.
It covers the basic composition, structure and properties of foods and the chemistry changes occurring during processing and utilization.
It also covers the chemistry of water, carbohydrates, proteins, lipids, vitamins, minerals and enzymes
fb.com/careeratfoodscience
Present status of Floriculture industry in Tamilnadu, India & World. All other aspects of floriculture industry including merits, demerits, oppurtunities, strategies to develop, potentials, scope etc..
chemistry project for class 12 on analysis of honeyRadha Gupta
this is a project for class 12 boards for chemistry subject on analysis of honey.it will be very helpful for students who are searching for chemistry project
The document discusses key aspects of the scientific method including observations, hypotheses, experiments, analysis, and theories. It explains that the scientific method involves making observations, asking questions, developing hypotheses, testing hypotheses through experiments, analyzing data, and drawing conclusions to support or revise hypotheses. The document also covers measurements and units in the metric system, significant figures, and basic calculations involving conversions between units.
01. basic concepts of chemistry 1(final)Anurag Bhatt
This document provides an overview of basic chemistry concepts including the branches of chemistry, units and standards used in chemistry, significant figures, and dimensions. It discusses the SI system of units, fundamental and derived units, and conversions between units. It also defines key chemistry terms like matter, elements, compounds, and mixtures. The document contains examples of calculations involving significant figures and dimensional analysis.
This document provides an overview of key concepts in chemistry. It discusses how chemistry connects the macroscopic world we experience to the microscopic world of atoms and molecules. Matter is composed of tiny particles called atoms, which combine to form molecules. A chemical reaction involves rearranging the way atoms are attached to each other. The three common states of matter are solids, liquids, and gases. Physical changes alter the form of matter without changing its chemical makeup, while chemical changes create new substances.
The document discusses units of measurement used in chemistry. It introduces common units like meters, liters, grams, seconds that are used to measure length, volume, mass and time. These units make up the International System of Units (SI) and metric system which are decimal systems used widely in science. Examples are given of measuring tools and conversions between units like inches to centimeters. Key types of measurements covered are length, volume, mass, temperature and time.
This document covers several topics related to measurement and error analysis in physics experiments. It begins by defining accuracy and precision, distinguishing between the two concepts. Accuracy refers to how close a measurement is to the true value, while precision describes the degree of variation in repeated measurements of the same quantity. It then discusses random and systematic errors, explaining that random errors vary unpredictably while systematic errors remain constant. The document provides examples of different types of systematic errors like instrumental, environmental, and observational errors. Finally, it introduces concepts like absolute error, relative error, and percentage error to quantify the uncertainty in measurements.
This document discusses measurement and units in science. It begins by defining measurement as reading tools like watches, scales, and thermometers. Standards of measurement are compared to a standard unit using tools. The metric system and SI units are introduced, with prefixes and conversions between units. Equalities show the same measurement in different units. Conversion factors relate different units, and steps for unit conversions in problems are outlined.
1. Chemistry is the study of matter and its properties and changes. It impacts many areas including health, energy, materials, food and agriculture.
2. Matter can be classified as elements, compounds or mixtures. Elements cannot be broken down further, compounds are made of two or more elements chemically bonded together, and mixtures maintain their individual identities.
3. The three main states of matter are solids, liquids, and gases. Physical and chemical changes alter or do not alter the composition of matter. The scientific method is used to study chemistry through observation, hypothesis, experimentation and theory development.
Capítulos 1 y 2 del libro de química de changyesu90uy
This document provides an overview of the development of atomic theory and models of the atom. It discusses key discoveries and experiments including:
- Dalton's atomic theory from 1808 that proposed atoms as fundamental particles and that elements are composed of unique atoms.
- J.J. Thomson's discovery in 1906 that the cathode rays were composed of negatively charged particles (electrons) much lighter than atoms.
- Rutherford's gold foil experiment from 1911 that showed the positive charge and most of the mass of atoms are concentrated in a very small nucleus.
- Chadwick's discovery of the neutron in 1932, which has no charge and a mass similar to protons.
- The modern definitions of atomic number as
1. The document discusses units of measurement and the SI system. It describes the seven base SI units including meters, kilograms, seconds, and kelvins.
2. Derived units are discussed along with examples like density. Significant figures and the accuracy and precision of measurements are also covered.
3. Errors in measurements are defined as the difference between experimental and accepted values. Percent error can quantify the accuracy of a measurement.
Here are the key rules for significant figures:
- Count all digits known with certainty
- Estimated digits are underlined or in parentheses
- Zeros between nonzero digits are significant
- Leading zeros are not significant
- Trailing zeros are significant if used to indicate a decimal
When performing calculations:
- The answer cannot be more precise than the least precise term
- Round answers to the least number of significant figures
The number of significant figures indicates the precision or uncertainty of a measurement. It provides important information about the reliability and reproducibility of experimental results.
the mathematics of chemistry stoichiometry dimensional analysis.pptjami1779
Here is a stoichiometry question I wrote for the given reaction:
If 3.25 grams of barium chloride are available to react, how many grams of barium sulfate can be produced?
The document provides an overview of fragrances chemistry and the perfume industry. It discusses:
- The history of perfumes and key ingredients like coumarin.
- How most luxury perfume brands outsource fragrance creation to large flavor and fragrance companies like Givaudan, Firmenich, and IFF.
- Techniques in fragrance chemistry like developing synthetic versions of rare and expensive natural ingredients to preserve resources and ensure sustainability and safety.
- The roles of different fragrance types (e.g. top notes, base notes) and molecules in constructing complex perfume accords and compositions.
The document summarizes key points about cooking methods and chemistry:
- It discusses two methods of tenderizing meat: hanging meat to age and using mechanical or chemical actions like beating or marinating.
- It explains how a pressure cooker works by raising the pressure above atmospheric pressure, increasing the boiling point of water and allowing food to cook faster while retaining more nutrients.
- It identifies starch and protein as major constituents in flour and describes how their structures are altered through processes like gelatinization and denaturation during cooking.
SOLID DISPERSION
Definition: The technology is the science of dispersing one or more active ingredients in an inert matrix in the solid stage.
Need of solid dispersion:
Increases Oral bioavailability of a drug
Increased dissolution rate.
Enhanced release of drugs from ointment.
Improved the solubility & stability.
The concept of solid dispersion was originally proposed by Sekiguchi & obi.
Increasing the dissolution, absorption & therapeutic efficacy of drugs in dosage forms.
Increasing solubility in water.
Improving the oral absorption and bioavailability of BCS Class II drugs.
The document discusses a study on enhancing the solubility of loratadine, a class II drug with low solubility and high permeability, through solid dispersion techniques. Loratadine's solubility decreases with increasing pH. The study prepares solid dispersions of loratadine with β-cyclodextrin, HPC, and PEG-6000 and finds their solubility is greatly improved, especially at higher pH levels. Solubility is tested in buffers from pH 1.2 to 7.4. The co-precipitation method provides better solubility results than physical mixing for the dispersions tested.
The document discusses solid dispersion and complexation techniques for improving the solubility and bioavailability of poorly soluble drugs. Solid dispersion involves combining a drug with a hydrophilic carrier to improve its dissolution rate. Types of solid dispersions include solid solutions, eutectic mixtures, and glass suspensions. Preparation techniques include hot melt, solvent evaporation, melt extrusion, and kneading. Complexation, such as drug-cyclodextrin inclusion complexes, enhances drug solubility and stability. These techniques are important for formulating oral drugs that are limited by poor solubility.
This document provides information about various chemicals and nutrients found in the kitchen. It discusses baking soda, vinegar, salt, citric acid, lye, bleach, water, and other common kitchen ingredients. It also covers macronutrients like carbohydrates, proteins, fats, and micronutrients like vitamins and minerals. Finally, it discusses starches and different types of cooking oils used in the kitchen.
Food Chemistry is the study of chemical processes and interactions of all biological and non- biological components of foods.
It covers the basic composition, structure and properties of foods and the chemistry changes occurring during processing and utilization.
It also covers the chemistry of water, carbohydrates, proteins, lipids, vitamins, minerals and enzymes
fb.com/careeratfoodscience
Present status of Floriculture industry in Tamilnadu, India & World. All other aspects of floriculture industry including merits, demerits, oppurtunities, strategies to develop, potentials, scope etc..
chemistry project for class 12 on analysis of honeyRadha Gupta
this is a project for class 12 boards for chemistry subject on analysis of honey.it will be very helpful for students who are searching for chemistry project
The document discusses key aspects of the scientific method including observations, hypotheses, experiments, analysis, and theories. It explains that the scientific method involves making observations, asking questions, developing hypotheses, testing hypotheses through experiments, analyzing data, and drawing conclusions to support or revise hypotheses. The document also covers measurements and units in the metric system, significant figures, and basic calculations involving conversions between units.
01. basic concepts of chemistry 1(final)Anurag Bhatt
This document provides an overview of basic chemistry concepts including the branches of chemistry, units and standards used in chemistry, significant figures, and dimensions. It discusses the SI system of units, fundamental and derived units, and conversions between units. It also defines key chemistry terms like matter, elements, compounds, and mixtures. The document contains examples of calculations involving significant figures and dimensional analysis.
This document provides an overview of key concepts in chemistry. It discusses how chemistry connects the macroscopic world we experience to the microscopic world of atoms and molecules. Matter is composed of tiny particles called atoms, which combine to form molecules. A chemical reaction involves rearranging the way atoms are attached to each other. The three common states of matter are solids, liquids, and gases. Physical changes alter the form of matter without changing its chemical makeup, while chemical changes create new substances.
The document discusses units of measurement used in chemistry. It introduces common units like meters, liters, grams, seconds that are used to measure length, volume, mass and time. These units make up the International System of Units (SI) and metric system which are decimal systems used widely in science. Examples are given of measuring tools and conversions between units like inches to centimeters. Key types of measurements covered are length, volume, mass, temperature and time.
This document covers several topics related to measurement and error analysis in physics experiments. It begins by defining accuracy and precision, distinguishing between the two concepts. Accuracy refers to how close a measurement is to the true value, while precision describes the degree of variation in repeated measurements of the same quantity. It then discusses random and systematic errors, explaining that random errors vary unpredictably while systematic errors remain constant. The document provides examples of different types of systematic errors like instrumental, environmental, and observational errors. Finally, it introduces concepts like absolute error, relative error, and percentage error to quantify the uncertainty in measurements.
This document discusses measurement and units in science. It begins by defining measurement as reading tools like watches, scales, and thermometers. Standards of measurement are compared to a standard unit using tools. The metric system and SI units are introduced, with prefixes and conversions between units. Equalities show the same measurement in different units. Conversion factors relate different units, and steps for unit conversions in problems are outlined.
1. Chemistry is the study of matter and its properties and changes. It impacts many areas including health, energy, materials, food and agriculture.
2. Matter can be classified as elements, compounds or mixtures. Elements cannot be broken down further, compounds are made of two or more elements chemically bonded together, and mixtures maintain their individual identities.
3. The three main states of matter are solids, liquids, and gases. Physical and chemical changes alter or do not alter the composition of matter. The scientific method is used to study chemistry through observation, hypothesis, experimentation and theory development.
Capítulos 1 y 2 del libro de química de changyesu90uy
This document provides an overview of the development of atomic theory and models of the atom. It discusses key discoveries and experiments including:
- Dalton's atomic theory from 1808 that proposed atoms as fundamental particles and that elements are composed of unique atoms.
- J.J. Thomson's discovery in 1906 that the cathode rays were composed of negatively charged particles (electrons) much lighter than atoms.
- Rutherford's gold foil experiment from 1911 that showed the positive charge and most of the mass of atoms are concentrated in a very small nucleus.
- Chadwick's discovery of the neutron in 1932, which has no charge and a mass similar to protons.
- The modern definitions of atomic number as
1. The document discusses units of measurement and the SI system. It describes the seven base SI units including meters, kilograms, seconds, and kelvins.
2. Derived units are discussed along with examples like density. Significant figures and the accuracy and precision of measurements are also covered.
3. Errors in measurements are defined as the difference between experimental and accepted values. Percent error can quantify the accuracy of a measurement.
Here are the key rules for significant figures:
- Count all digits known with certainty
- Estimated digits are underlined or in parentheses
- Zeros between nonzero digits are significant
- Leading zeros are not significant
- Trailing zeros are significant if used to indicate a decimal
When performing calculations:
- The answer cannot be more precise than the least precise term
- Round answers to the least number of significant figures
The number of significant figures indicates the precision or uncertainty of a measurement. It provides important information about the reliability and reproducibility of experimental results.
the mathematics of chemistry stoichiometry dimensional analysis.pptjami1779
Here is a stoichiometry question I wrote for the given reaction:
If 3.25 grams of barium chloride are available to react, how many grams of barium sulfate can be produced?
This document provides an overview of chemistry concepts including:
- Chemistry is the study of matter and its properties, covering topics like health, energy, materials, food and more.
- Matter is anything that has mass and takes up space, and can exist as elements, compounds and mixtures.
- Chemical and physical changes alter substances in different ways. The document also introduces concepts such as states of matter, properties of matter, units of measurement, and dimensional analysis.
This document discusses measurement, density, and temperature scales. It defines qualitative and quantitative measurements. It explains scientific notation and how to convert between standard and scientific notation. It discusses accuracy versus precision. It describes metric units and prefixes for length, mass, volume, and temperature. It provides examples of calculating density and solving density problems using dimensional analysis. Finally, it introduces the Fahrenheit, Celsius, and Kelvin temperature scales.
This document contains a summary of a physics test covering topics in chapter 1 on introduction to physics. The test contains multiple choice and short answer questions on topics like base and derived quantities, units, measuring instruments, scientific investigation and graphs. It provides the context of a test being given to assess students' understanding of fundamental physics concepts introduced in chapter 1.
This document provides an overview of key concepts in chemistry including:
1. It introduces significant figures and the rules for determining how many figures are meaningful in measurements and calculations.
2. It describes the scientific method as a cycle of making observations, forming hypotheses, designing experiments to test hypotheses, and using results to develop theories or laws.
3. It outlines the metric system and prefixes used to modify base units of measurement like grams, meters, and liters.
The document discusses units of measurement in the International System of Units (SI). It describes the seven base SI units including the meter, kilogram, second, ampere, kelvin, mole and candela. It also discusses derived units such as volume, density and temperature. Units are based on multiples of ten to allow for easy conversion between units. Common prefixes are used to indicate multiples and fractions of units.
The document discusses units of measurement in science, focusing on the International System of Units (SI). It describes the seven base SI units including the meter for length, kilogram for mass, second for time, and kelvin or degree Celsius for temperature. The document provides examples of common metric prefixes and derived units, explaining relationships between units of volume, mass, energy and other quantities. It emphasizes that the SI system is based on multiples of ten, making conversions between units easy.
The document discusses units of measurement in the International System of Units (SI) and their use in science. It describes the seven base SI units including the meter, kilogram, second, ampere, kelvin, mole and candela. It also discusses derived units such as volume, density and temperature. Units are based on multiples of ten to allow for easy conversion between units. Common prefixes are used to indicate multiples and fractions of units.
This document provides an overview of the major topics in Earth Science, including the four main areas of study: geology, meteorology, astronomy, and oceanography. It defines Earth Science as the study of Earth and its processes, then describes each of the four areas in 1-2 sentences. For example, geology is defined as the study of Earth and its matter, processes, and history. The document also briefly introduces other key concepts in Earth Science, such as scientific measurement units and the scientific method.
The document provides information about metric conversions and the metric system. It includes:
- Metric units are based on powers of ten and the metric system aims to have a single unit for any physical quantity without needing conversion factors.
- Examples are provided for converting between common metric units like centimeters, meters, kilometers, liters, grams, and Celsius and Fahrenheit temperatures.
- The importance of accurate conversions is discussed through examples of cargo errors, plane crashes, medical errors, and spacecraft losses due to conversion mistakes between metric and U.S. customary units.
Similar to Que es la Química, Método Científico (20)
19. 7 Learning Check Which of the following items contain chemicals? A. Fertilizers B. Vitamins C. Happiness D. Iron nails E. Paints
20. 8 Solution Which of the following items contain chemicals? A. Fertilizers contain chemicals B. Vitamins contain chemicals C. Happiness does not contain chemicals D. Iron nails contain chemicals E. Paints contain chemicals
21. Substance Substance- chemical that consists of one type of matter and always has the same composition and properties 9
24. 13 Everyday Scientific Thinking Observation:The sound from a CD in a CD player skips. Hypothesis 1:The CD player is faulty. Experiment 1: When I replace the CD with another one, the sound from this second CD is OK. Hypothesis 2:The original CD has a defect. Experiment 2:When I play the CD in another player, the sound still skips. Theory: My experimental results indicate the original CD has a defect.
25. Scientific method State the problem (like a question) Hypothesis (suggest an answer to a problem) (If _ind var___ then _dep var___) Plan experiment Gather data Interpret data (look for patterns or trends) Conclusion, plan future work Publish results
26. Experiment Way of testing a hypothesis Has an independent and a dependent variable Independent variable- you define it, causes a change in another Dependent variable- changes in response to the ind. Var. Control group - reference to find out if there were any changes in the experimental groups.It has all the same elements except the Ind. Var
27. Tránsito de San Pedro wants to establish if the installation of radars will affect the average velocity of cars driving through MoronesPrieto. establish the problem (Will radars affect the velocity of cars?) Present the hypothesis (If there are radars in specific locations then cars will decrease their speed) Design the experiment (install radars in locations and measure speed with and without radars) identify independent (radars in specific locations) dependent variable (speed of cars) state the control group. (locations without radars)
28. Carol is a soccer player. She told Mark that Adidas training shoes have a greater performance than Nike training shoes, in the soccer field. establish the problem Present the hypothesis Design the experiment identify dependent and independent variable state the control group.
29. 18 Learning Check The step of scientific method indicated in each is 1) observation 2) hypothesis 3) experiment 4) theory A. A blender does not work when plugged in. B. The blender motor is broken. C. The plug has malfunctioned. D. The blender does not work when plugged into a different outlet. E. The blender needs repair.
30. 19 Solution The step of scientific method indicated in each is 1) observation 2) hypothesis 3) experiment 4) theory A. (1) A blender does not work when plugged in. B. (2) The blender motor is broken. C. (2) The plug has malfunctioned. D. (3) The blender does not work when plugged into a different outlet. E. (4) The blender needs repair. Cw-Do from page 9 problems: 1.12-1.14
38. 23 Stating a Measurement In a measurement, a number is followed by a unit. Observe the following examples of measurements: Number Unit 35 m 0.25 L 225 kg 3.4 hr
55. 30 For each of the following, indicate whether the unit describes 1) length, 2) mass, or 3) volume. ____ A. A bag of onions has a mass of 2.6 kg. ____ B. A person is 2.0 m tall. ____ C. A medication contains 0.50 g aspirin. ____ D. A bottle contains 1.5 L of water. Learning Check
56. 31 For each of the following, indicate whether the unit describes 1) length, 2) mass, or 3) volume. 2 A. A bag of onions has a mass of 2.6 kg. 1 B. A person is 2.0 m tall. 2 C. A medication contains 0.50 g aspirin. 3 D. A bottle contains 1.5 L of water. Solution
57. 32 Learning Check Identify the measurement with an SI unit. A. John’s height is 1) 1.5 yd 2) 6 ft 3) 2.1 m B. The race was won in 1) 19.6 s 2) 14.2 min 3) 3.5 hr C. The mass of a lemon is 1) 12 oz 2) 0.145 kg 3) 0.6 lb D. The temperature is 1) 85C 2) 255 K 3) 45F
58. 33 Solution Identify the measurement with an SI unit. A. John’s height is 3) 2.1 m B. The race was won in 1) 19.6 s C. The mass of a lemon is 2) 0.145 kg D. The temperature is 2) 255 K
59. 34 STEP 1 State the given and needed units. STEP 2 Write a plan to convert the given unit to the needed unit. STEP 3 Write equalities/conversion factors that connect the units. STEP 4 Set up problem with factors to cancel units and calculate the answer. Unit 1 x Unit 2 = Unit 2 Unit 1 Given Conversion Needed unit factor unit Guide to Problem Solving (GPS)
61. 36 A rattlesnake is 2.44 m long. How long is the snake in centimeters? 1) 2440 cm 2) 244 cm 3) 24.4 cm Learning Check
62. 37 A rattlesnake is 2.44 m long. How long is the snake in centimeters? 2) 244 cm given conversion needed unit factor unit 2.44 m x 100 cm = 244 cm 1 m Solution
63.
64. 39 How many minutes are in 1.4 days? Given unit: 1.4 days Needed unit: min Plan: days hr min Equalties: 1 day = 24 hr 1 hr = 60 min Set up problem: 1.4 days x 24 hr x 60 min = 2.0 x 103 min 1 day 1 hr Example: Problem Solving
65.
66. The units in the conversion factors must cancel to give the correct unit for the answer. What is wrong with the following setup?1.4 day x 1 day x 1 hr 24 hr 60 min Units = day2/min is Not the needed unit Units don’t cancel properly. Check the Unit Cancellation
67. More units Area m2 = m x m Volume m3 = m x m x m Density mass/volume g/mL or Kg/L 41
68. K = oC + 273 Ex 23 oC = _______ K 135 K = ________ oC 1L = 1 dm3 1 m3 =1000L Ex 27 m3 = ________ L 42
69. 43 Osmium is a very dense metal. What is its density in g/cm3 if 50.0 g of osmium has a volume of 2.22 cm3? 1) 2.25 g/cm3 2) 22.5 g/cm3 3) 111 g/cm3 Learning Check
70. 44 Given: mass = 50.0 g volume = 2.22 cm3 Plan: Write the density expression. D = mass volume Express mass in grams and volume in cm3mass = 50.0 g volume = 2.22 cm3 Set up problem using mass and volume. D = 50.0 g = 22.522522 g/cm3 2.22 cm3 = 22.5 g/cm3 Solution
83. 54 Comparing Numbers in Standard and Scientific Notation Number in Standard Format Scientific Notation Diameter of the Earth 12 800 000 m 1.28 x 107 m Mass of a human 68 kg 6.8 x 101 kg Mass of a hummingbird 0.002 kg 2 x 10-3 kg Length of a pox virus 0.000 000 3 cm 3 x 10-7 cm
84. 55 Learning Check Select the correct scientific notation for each. A. 0.000 008 1) 8 x 106 2) 8 x 10-6 3) 0.8 x 10-5 B. 72 000 1) 7.2 x 104 2) 72 x 103 3) 7.2 x 10-4
85. 56 Solution Select the correct scientific notation for each. A. 0.000 008 2) 8 x 10-6 B. 72 000 1) 7.2 x 104
86. 57 Learning Check Write each as a standard number. A. 2.0 x 10-2 1) 200 2) 0.00203) 0.020 B. 1.8 x 105 1) 180 000 2) 0.000 0183) 18 000
87. 58 Solution Write each as a standard number. A. 2.0 x 10-2 3) 0.020 B. 1.8 x 105 1) 180 000