home

=__Period C Chemistry__= Editor: Evan Grandfield

Section 1.1-Chemistry pg. 7-11: Nina Demeo (coeditor), Christos Anastos Section 1.2-Chemistry Far and Wide pg. 12-17: Kendyl Barron (coeditor), Steven Denison Section 1.3-Thinking like a Scientist pg. 20-27: Courtney Gareau (coeditor), Maggie Bie Section 1.4-Problem Solving in Chemistry pg. 28-32: Adam Shanahan (coeditor), Heather Bowditch Section 3.1-Measurements and their Uncertainty pg. 63-72: Andrew Sciotti (coeditor), Tom DeMarco Section 3.2-International System of Units (SI) pg. 73-79: Eileen Corkery (coeditor), Katherine Perry Section 3.3-Conversion Problems pg. 80-87: Marion Burdick (coeditor), Mike McShane Section 3.4-Density pg. 89-83: Liz Sieber (coeditor), Nick Brault

Introduction to the Wiki: This page has been constructed on the first and third chapters of Prentice Hall's //Chemistry// textbook. The first chapter is an introduction into chemistry and deals primarily with the fundamental applications, uses, topics, history, and methods of the subject. The scientific method as well as problem-solving methods are outlined with particular care due to their integral nature in chemistry. The third chapter deals with scientific measurement in chemistry and demonstrates basic ways of problem-solving through dimensional analysis. It takes care to define the SI units as well as to educate on the procedure for interpreting and understanding significant figures. This wiki-page outlines the chapter in its entirety, and has included all information crucial to the understanding of these chapters.

__**Section 1.1 - Chemistry**__ **-** Nina DeMeo and Christos Anastos

Key Concept: Because living and nonliving things are made of matter, chemistry affects all aspects of life and most natural events. - Matter is anything that has mass and occupies space. - Chemistry is the study of the composition of matter and the changes it undergoes. Key Concept: Five traditional areas of study are organic chemistry, inorganic chemistry, biochemistry, analytical chemistry, and physical chemistry. - Organic chemistry is the study of all chemicals containing carbon (with a few exceptions) - Inorganic chemistry is the study of chemicals that, in general, do not contain carbon - Biochemistry is the study of processes that take place in organisms (including muscle contraction, digestion, etc.)  -Analytical chemistry is the area of study that focuses on the composition of matter -Physical chemistry is the area that deals with the mechanism, the rate, and the energy transfer that occurs when matter undergoes a change
 * __What is chemistry?__**
 * does not have to be seen; example: air
 * can explain different aspects of our life / in the world
 * __Areas of Study__**
 * found mainly in non-living things(like this rock)
 * example: measuring the level of lead in drinking water

-the boundaries between each category are not firm, therefore chemists usually study in multiple areas at any given time Key Concept: Pure research can lead directly to an application, but an application can exist before research is done to explain how it works - Pure Chemistry is the pursuit of chemical knowledge for its own sake - Applied Chemistry is research that is directed toward a practical goal or application -pure and applied chemistry are often linked -studying things such as silk (which led to the discovery of nylon) and aspirin, led to knowledge of their applications Technology is the means by which a society provides its members with those things needed and desired Key Concept: Chemistry can be useful in explaining the natural world, preparing people for career opportunities, and producing informed citizens. __Explaining the Natural World__ -Chemistry can help people understand how things in the world work __Preparing for a Career__ -a person doesn't necessarily need to be a chemist to benefit from knowing chemistry -many different careers require a knowledge of chemistry such as firefighters, turf managers, and photographers __Being an Informed Citizen__ -people will need to make choices that will influence the development of technology; by having an understanding of chemistry, people can evaluate the data presented and, from there, make informed decisions
 * __Pure and Applied Chemistry__**
 * done to answer a specific question
 * the development of nylon (pictured below) and the use of aspirin (also pictured below) belong to a system of applied science known as **technology**
 * allows things to be done more quickly, with less effort, or to do things otherwise impossible without technology
 * __Why Study Chemistry?__**
 * Examples: Why apples turn brown upon exposure to air; why water expands as it freezes; etc...
 * learning chemisry can allow you to go into a job as a chemist, although it can help with other fields too.

﻿**__Section 1.2 Chemistry Far & Wide__** by Kendyl Barron(co-editor) and Steven Denison

__Materials__- Kendyl Barron
 * Chemists design tools in relaiton to their determined purpose or need.


 * There are two different view points one can take in looking at the world around us: one of a __macroscopic universe__ and one of a __microscopic universe.__


 * In a macroscopic universe //objects are large enough to see with the unaided eye.// In the microscopic universe //objects can only be seen under magnification.//

__Energy__- Kendyl Barron
 * With the size of our modern population, energy is being consumed and needed now more than ever. To meet the demand for energy, as a society we must conserve and produce more energy than we consume. It is the job of many scientists to develop new ways to conserve, produce, and store different energies.

-->**Conservation**: Through __insulation,__ such as the insulation of a house to keep in heat, energy is saved. Insulation is a //material that works as a barrier to heat flow.//

--> **Production**:


 * Energy and fuel is produced by way of burning fossil fuels such as //coal, petroleum, and natural gases//. These specific materials are the remains of ancient organisms, therefore supply is limited.
 * New biofuel developements include //soybean biodiesel, corn-based fuels, and algae fuel as awell as other hybrid fuels//.
 * Biofuel is also believed to be healthier for the environment in comparison to fossil fuels.

--> **Storage**: Batteries of all sizes and powers are a main source of storage of produced or conserved energy. Chemicals store electrical currents that may be released upon usage. Some batteries are able to be recharged with energy and supply energy for wireless technology.

__Medicine & Biotechnology__- Kendyl Barron


 * The field of Chemistry has made important advacnes in //medical techniques, materials and drugs, and technologies and equipments//. __Biochemists__ often supply research and developments in the field of medicine. Biologists, doctors, and chemists all work together to better understand the human body and the chemical reactions that take place within in.

-->**Medicines:** __Presciption drugs__ are formulated to combat various diseases, infections, and conditions. __Over the counter medications__ combat nonspecific symptoms of minor illneses. //Drugs and medicines interact in a specific way with cells and chemicals within the body.// Understanding the chemicals of the body help develop more effective medicines.

-->**Materials:** Chemistry has also develped ways //__to repair and replace__// parts of the body and their functions. Replacemnet parts include plastic tubing to repair damaged arteries and artificial joints, bones, limbs, and even skin.

-->**Biotechnology:** Biotechnology is applied science of living things and biological processes to aid in developments in engineering, technology, and medicine. //Biotechology plays an important role in genetic engineering//. Many chemists have become part of the Human Genome Project, and international research study working towards mapping the "human genome". Other chemists have done imporant work in DNA research. media type="youtube" key="gkQJ26DAxfs?fs=1" height="385" width="480" align="center"

__Agriculture__ - Steven Denison
- In order to feed the increasing population chemists will need to find ways to make agriculture easier, and more effective. - This can be done through several different ways

--> **Productivity:** Because certain factors such as soil quality, lack of water, and disease can decrease the productivity of a farm, chemists are hard at work trying to counteract these problems. They can see if the soil has the appropriate chemicals for growing a crop and can help engineer plants that help reduce water usage.

--> **Crop Protection:** Due to advances in multiple fields, farmers can begin to use certain chemicals to protect their crops. These chemicals only target a specific insect that hurts a specific crop. Chemists have helped create these chemicals which has helped increase crop survivability.

__The Environment__ - Steven Denison
-As new chemicals are created and used the environment is getting affected by newly created __pollutants__. A __pollutant__ is a material that is harmful to humans, plants, or other organisms.

--> **Identify Pollutants:** Lead was the most common pollutant throughout history, and still remains so today. Lead in increasing levels can do severe damage to the human body and other organisms.

--> **Prevent Pollution**: The use of lead paint in houses was banned in 1978. However lead-poisoning is still around because lead can be found in paints and other household materials. Although lead usage has gone down significantly throughout the world, it is still around and harmfull.

__The Universe__ - Steven Denison
-Scientists have used the methods that they use to study the Earth to study other parts of the galaxy. To study the universe they gather information about faraway places and analzye it here on Earth.

- In the early 1800s scientists analyzed light to find out the composition of stars.

- In order to analyze planets and moons, scientists study their matter. They do this through materials brought back to Earth or through probes. By analyzing large rocks they can find out the conditons on the planet or moon during the time of the rocks' formation.

__**Section 1.3 Thinking Like a Scientist - Courtney Gareau (Co-editor) and Maggie Bie**__

__Alchemy - Maggie Bie__

Key Concept - Alchemists developed the tools and techniques for working with chemicals.

[[image:http://i99.photobucket.com/albums/l310/PlayerEntity/Alchemy/alchemy-symbols.gif width="248" height="327"]] Common symbols for elements used in alchemy
I. Practical Side
 * working with:
 * metals
 * dyes
 * glass

II. Mystical Side III. Tools and Techniques: Developed processes for separating mixtures and purifying chemicals
 * ====Focused on concepts like perfection ====
 * gold seen as perfect metal
 * alchemists tried to make other materials (e.g. lead)
 * their work sparked chemistry
 * beakers
 * flasks
 * tongs
 * funnels
 * motar and pestle

__An Experimental Approach to Science - Maggie Bie__

Key Concept **-** Lavoisier helped to transform chemistry from a science of observation to a science of measurement I. Alchemy to Science Science flourished in Britian because of the support of King Charles II
 * The Royal Society of London for the Promotion of Natural Knowledge
 * met to discuss scientific topics and conduct experiments
 * aimed to encourage scientists to base conclusions about natural world on experimental evidence (not philosophical debates)

II. Antoine- Laurent Lavoisier Lavoisier and his wife, Marie Anne (she made drawings of his experiments and translated scientific papers)
 * Changed the explanation of how materials burn
 * accepted explanation was: materials burn because they contain phlogiston
 * this required ignoring that metals can gain mass (while burning)
 * Lavoisier knew the two main gases in air were oxygen and nitrogen
 * He proved oxygen is needed for a material to burn
 * To finance his experiments, Lavoisier was a member of the royal taxation committee
 * He was targeted by those involved in the French Revolution.
 * In 1794, he was arrested, tried, and beheaded

__The Scientific Method - Courtney Gareau__

Key Concept: Steps in the scientific method include making observations, testing hypotheses, and developing theories.

Scientific Method - a logical, systematic approach to the solution of a scientific problem. Observation – information obtained through the senses; observation in science often involves a measurement. This is the first step to make an observation. Next, form a hypothesis. Hypothesis – a proposed explanation for an observation Experiment – a procedure that is used to test a hypothesis Third, you experiment. When experimenting, you deal with different variables: Manipulated variable – the independent variable; the variable that you change during an experiment Responding variable – the dependent variable; the variable that is observed during the experiment For results to be accepted, the experiment must produce the same results, no matter how many times the experiment is performed or by whom.

The next step in the scientific method is developing theories, which takes place after a hypothesis meets the test of repeated experimentation. Scientists say that a theory can never be proved because they want to leave open the possibility that the theory may need to be changed to explain new observations or experimental results. Theory – a well-tested explanation for a broad set of observations Scientific experiments can lead to scientific laws. Scientific Law – a concise statement that summarizes the results of many observations and experiments

__Collaboration and Communication - Courtney Gareau__

Key Concept: When scientists collaborate and communicate, they increase the likelihood of a successful outcome. Collaboration is an important part of science. Collaboration is important because sometimes no one scientist has enough knowledge, skills, or resources to solve the problem. Scientists from different fields are needed to provide insight into a problem. Another type of collaboration is when an industry funds research in return for ideas and expertise from the researchers. Collaboration is not always easy; conflicts can arise regarding resources, amount of work, receiving credit, and publishing.

Communication is another important part of science. Scientists communicate face to face or via e-mail, phone, and at international conferences. Also, journals are published and the articles in journals are the most reliable source of information because the work as been reviewed by experts in the field before it was published. The internet is also a great resource because anyone can access the information, but it isn’t good because people can post things with out having the information reviewed. Example of a Science Journal


 * __Section 1.4 Problem Solving in Chemistry- pages 28-32- Adam Shanahan and Heather Bowditch__**


 * Problem solving skills- page 28**

In order to effectively solve a problem, one must develop and implement a plan.


 * Solving Numeric Problems- pages 29-30**

There are three steps to solving numberic problems.
 * 1) Analyze - Identiy where you are starting (known), and where you are going (unknown). If the answer will be a number then identify the units you will use. Finally, make a plan to get the answer.
 * 2) Calculate - Self explanatory
 * 3) Evalulate - Check to make sure that the answer makes sense. If it does not, then reword the answer. Then check for mistakes and round off the numbers by writing up to one decimal point and estimating the second decimal point.

Example problem from the book - You are walking from the Indiana state Capital to the Murat centre which is 8 blocks away. How many minutes will the it take you if you walk 1 mile in 20 minutes. Assume that 10 short city blocks equals one mile. Knowns - Distance to be traveled= 8 blocks Walking speed= 1 mile/ 20 minutes 1 mile= 1 block Unknown- amount of minutes to complete the trip 8 block x 1 mile/10 blocks = 0.8 miles 0.8 miles x 20 minutes/1 mile = 16 minutes. The answer is 16 minutes to walk 8 short blocks which is reasonable, the answer has the correct unit, and the relationships used are correct.
 * Analyze**
 * Calculate**
 * Evalulate**

Conceptual problems are non-numerical problems. You must first check for known and unknown and make a plan, then analyze, and finally solve.
 * Solving Conceptual Problems - pages 31-32**

Sample problem from the book - Manny must get a haircut, wash his car, buy some groceries, buy stamps, rent a video, and return some library books between 10 and 5. The barbershop is open rom 10 am to 3 pm. The carwash is open rom 10 am to 4 pm. The grocery store is open from 7 am to midnight. The post office is open from 8 am to 11 am. The video store is open from 10 am to 6 pm. The library is open from 10 am to 1 pm. Each errand takes 30 minutes and manny will only do one errand per hour. Manny will also have a lunch break between 12 and 1. Find out a way for Manny to complete his tasks. Each place Manny must go to is open for a limited number of hours. Manny must do his errands between 10 and 12, and 1 and 5. At a rate of one errand per hour, Manny must do 2 errands before lunch and 4 ater. The post ofice and library are only open in the morning. The barbershop and carwash close earlier than the video store. The supermarket is open late. One possible order for the errands is post office, library, barbershop, car wash, video store, and supermarket.
 * Analyze**
 * Solve**

__**Section 3.1 - Measurements and Their Uncertainty (Pages 63-72) - Andrew Sciotti and Tom DeMarco**__

I**. Using and Expressing Measurements** (page 63) - Tom DeMarco  -Key Concept: Measurements are fundamental to the experimental sciences. For that reason, it is important to be able to make measurements and to decide whether a measurement is correct.

-A ** measurement ** is a quantity that has both a number and a unit. Measurements can help you use the correct amount of ingredients when baking or determining what to wear based on the temperature.

-** Scientific Notation **is writing a given number as the product of two numbers: a coefficient and 10 raised to a power.

-In chemistry, you will often come across very large or very small numbers. To make these numbers easier to write and comprehend, scientific notation is used. When using large numbers the number is written like this: 2.03 x 10^6. That represents the number 2,030,000. The same approach is made with decimal numbers less than 1.

Scientific Notation Practice Solve each problem, and express your answer in correct scientific notation. a) (8.0 x 10^-2) x (7.0 x 10^-5) b) (7.1 x 10^-2) + (5 x 10^-3) Solutions: a) 5.6 x 10^-6 b) 7.6 x 10^-2 II. **Accuracy, Precision, and Error** (Pages 64 - 65) - Andrew Sciotti

=== __Accuracy and Precision__ (Page 64) ** Accuracy **: A measure of how close or far an experimental value may be from the actual value or true value. ** Precision **: How consistent a series of values are in a set/experiment. To evaluate the accuracy of a measurement, the measured value must be compared to the correct value. To evaluate the precision of a measurement, you must compare the values of two or more repeated measurements. **Example of Accuracy and Precision**: Darts is a great example of Accuracy and Precision. If you can hit the bulls-eye many times repetitively then you have great accuracy and precision. But if you hit near the edge in the same spot many times you have high precision but low accuracy. If you hit close to the bulls-eye but in many different places then you have low precision but high accuracy. If you hit the dartboard in many different places you have both low accuracy and low precision. Instructional Video: Accuracy vs. Precision media type="youtube" key="5APhVxCEPFs?fs=1" height="385" width="640" Practice for Accuracy vs. Precision  === [] **Just the Diagram with the targets**

 __Determining Error__ (Page 65) Formula for Error: Error = experimental value – accepted value Error can be positive or negative, but by using the percent error it is much easier to tell the difference. Formula for Percent Error: Percent Error = (|experimental value – accepted value| /accepted value) x 100% Example of Percent Error: The teacher gave the class 3 minutes for everyone to measure the height of a desk. Ron decided to talk with friends for 2 and one half minutes and then quickly measured the desk. Ron measured that the desk was 10” tall when the teacher knew it was really 12”. Error: 10 inches – 12 inches Error = -2 inches
 * Accepted Value **: The correct value based on reliable sources.
 * Experimental Value **: Value measured in the lab (not always accepted value)
 * Error **: Difference between experimental value and the accepted value.
 * Percent Error **: Absolute value of the error divided by the accepted value multiplied by 100%.


 * This is hard to tell the actual error so we use the Percent Error*

Percent Error = (|10-12| /12 x 100 Percent Error = (|-2| /12) x 100 Percent Error = .166 x 100 Percent Error = 16.6

Instructional Video: Percent Error: media type="youtube" key="h--PfS3E9Ao?fs=1" height="385" width="640" Practice for Percent Error [] Error = experimental value – accepted value

**III. Significant Figures in Measurements **(Pages 66 - 67) - Tom DeMarco** **   -Key Concept: Measurements must always be reported to the correct number of significant figures because calculated answers often depend on the number of significant figures in the values used in the calculation.

-The ** significant figures ** in a measurement include all of the digits that are known, plus a last digit that is estimated. If you have a measured weight known to be between 2.4 lb and 2.5 lb and you have estimated it to be 2.46 lb there are three significant figures. The digits 2 and 4 are known with certainty whereas the last digit, 6, is estimated. They are all significant figures because each digit conveys useful information.

-The rules for determining whether a digit in a measured value is significant are: 1. Every nonzero digit in a reported measurement is assumed to be significant. a. The measurements 24.7 meters, 0.742 meter, and 714 meters each express a measure of length to three significant figures.

2. Zeros appearing between nonzero digits are significant. a. The measurements 7003 meters, 40.79 meters, and 1.503 meters each have four significant figures.

3. Leftmost zeros appearing in front of nonzero digits are not significant. They act as placeholders. a. The measurements 0.0071 meter, 0.42 meter, and 0.000099 meter each only have two significant figures. The zeros to the left are not significant. By writing the measurements in scientific notation, you can eliminate such placeholding zeros: in this case, 7.1 x 10^-3 meter, 4.2 x 10^-1 meter, and 9.9 x 10^-5 meter.

4. Zeros at the end of a number and to the right of a decimal point are always significant. a. The measurements 43.00 meters, 1.010 meters, and 9.000 meters each have four significant figures.

5. Zeros at the rightmost end of a measurement that lie to the left of an understood decimal point are not significant if they serve as placeholders to show the magnitude of the number. a. The zeros in the measurements 300 meters, 7000 meters, and 27,210 meters are not significant figures. For example, if all of the zeros in the measurement 300 meters were significant, writing the value in scientific notation as 3.00 x 10^2 meters makes it clear that these zeros are significant.

6. There are two situations in which numbers have an unlimited number of significant figures. The first involves counting. The second involves exactly defined quantities such as those found within a system of measurement. a. Counting: If you count 23 people in your classroom, the there are exactly 23 people, and this value has an unlimited number of significant figures. b. Defined Quantities: When you write 60 min = 1 hr, or 100 cm = 1 m, each of these numbers has an unlimited number of significant figures. c. Exact quantities do not affect the process of rounding an answer to the correct number of significant figures.

IV. **Significant Figures in Calculations** (Pages 68-72) - Andrew Sciotti

=== __Rounding__ (Page 68-69) Significant Figure : The number of figures in a result that has a degree of reliability. Quick Example: The number 13.2 has 3 significant figures, the number 13.20 has 4. ** How to Round a Number ** ===
 * To round you must decide upon how many significant figures there should be in the answer.
 * This decision depends on the measurements and the process used to get the answer.
 * Once you figure out the number of significant figures your answer should have, you can start to round, starting at the left side of the number.
 * If the digit on the right of the least significant digit is less than 5 then the least significant digit stays the same and that number is droped
 * If the digit on the right of the leasst significant digit is greater than or equal to 5 you drop the number and increase the least significant digit by 1


 * Examples of Rounding**:

a) Round 314.731 meters (four) 314.__7__31 - Since 3 is less than 5 you don't round up Answer = 314.7 meters

b) Round 0.0017836 (four) 0.00178__3__6 - Since 6 is greater than 5 you round up (0's between decimal point and first significant number don't count) Answer = 0.001784

Practice Problems:

a) Round 103515.854074 (six)

b) Round 65.612 (four)

c) Round 0.07123 (two)

a) 103,516 b) 65.61 c) 0.071
 * Answers**

__Addition and Subtraction__ (Page 70)

Round addition or subtraction calculations to the name number of decimal places as the measurement with the least number of decimals.

__**Example**__:

12.765 78.1 <--- least number of decimals 43.122 = 133.__9__87 (Round to underlined number, 8 is greater than 5 so 9 turns to 10 which makes 133 turn to 134) Rounded to: 134
 * Addition**:

__**Practice**:__ 875.123 + 15.1 + 7 = ? = (rounded to) ?

Subtraction is exactly the same as addition


 * __Multiplication and Division__** (Page 71)

To round with multiplication and division you need to round the answer to the same number of significant figures as the measurement with the least number of significant figures.

__**Example**:__

7.55 meters x 0.34 meter = 2.567 meter squared = 2.6 meters squared - 0.34 meter has two significant figures so you round to the second one
 * Multiplication**:

__**Practice**:__ 2.10 meters x 0.70 meter = ? = ?
 * Multiplication**:

2.4526 meters / 8.4 = 0.291 976 meter = 0.29 meter - 8.4 has two significant figures so you round to the second one
 * Division**:

__**Practice**:__ 2.12345 / 5.17 = ? = ?

Video for All Rounding (Don't Worry About Counting)

media type="youtube" key="-xDGNP4pPKw?fs=1" height="385" width="640"

Section 3.2 -The International System of Units - Key Concepts, charts, and vocabulary //by Katherine Perry//- Bulleted notes, pictures, video, and links //by Eileen Corkery//

I. Measuring with SI Units __~Key Concept:__ __The five SI base units commonly used by chemists are the meter, the kilogram, the kelvin, the second, and the mole.__
 * // The International System of Units //is a revised version of the metric system, adopted by international agreement in 1960.
 * All metric units are based on multiples of 10, so they can be converted easily.


 * There are seven SI base units:


 * = **Quantity** ||= **SI base unit** ||= **Symbol** ||
 * = Length ||= meter ||= m ||
 * = Mass ||= kilogram ||= kg ||
 * = Temperature ||= kelvin ||= K ||
 * = Time ||= second ||= s ||
 * = Amount of substance ||= mole ||= mol ||
 * = Luminous intensisty ||= candela ||= cd ||
 * = Electric current ||= ampere ||= A ||


 * **Commonly Used Metric Prefixes** ||
 * **Prefix** || **Meaning** || **Factor** ||
 * mega (M) || 1 million times larger than the unit it precedes || 10^6 ||
 * kilo (k) || 1000 times larger than the unit it precedes || 10^3 ||
 * deci (d) || 10 times smaller than the unit it precedes || 10^-1 ||
 * centi (c) || 100 times smaller than the unit it precedes || 10^-2 ||
 * milli (m) || 1000 times smaller than the unit it precedes || 10^-3 ||
 * micro (//µ//) || 1 million times smaller than the unit it precedes || 10^-6 ||
 * nano (n) || 1000 million times smaller than the unit it precedes || 10^-9 ||
 * pico (p) || 1 trillion times smaller than the unit it precedes || 10^-12 ||

II. Units and Quantities ~Key Concept
 * Common metric units of length include the centimeter, meter, and kilometer.


 * Centimeter= 1/100 of a meter (width of a shirt button)
 * Meter= base unit (height of a doorknob from floor- a little more than a yard if you want to use customary units of measurement)
 * Kilometer= 1,000 meters (about five city blocks)

~Key Concept: Common metric units of volume include the liter, milliliter, cubic centimeter, and microliter.
 * Liter=base unit (1 quart of milk)
 * Millimeter= 1/1,000 of a liter (20 drops of water)
 * Cubic centimeter= 1/100 of a liter (a cube of sugar)
 * Microliter= 1 millionth of a liter (crystal of table salt)

~Key Concept : Common metric units of mass include the kilogram, gram, milligram, and microgram.
 * Kilogram=base unit (small textbook, or about 2lbs in customary units)
 * Gram= 1/1,000 of a kilogram (a dollar bill)
 * Milligram= 1/1000 of a gram
 * Microgram= 1/1,000,000 of a milligram

~Key Concept
 * Common metric units of energy include the joule and the calorie.

III. Vocabulary& Terms to Know

~Meter (m) -is the basic unit of length, or linear measure, in SI.

~Liter (L) -is the volume of a cube that is 10 centimeters along each edge.

~Kilogram (kg) -is the basic SI unit of mass.

~Gram (g) -is 1/1000 of a kilogram. __-The mass of 1 cm^3 of water at 4 degrees Celsius is 1 g.__

~Weight -is the force that measures the pull on a given mass by gravity. __-Weight can change (if your on the moon for example) but mass will stay the same no matter where you are, even if it's Pluto.__

~Temperature -is a measure of how hot or cold an object is. __-An object's temperature determines the direction of heat transfer. (hot to cold)__ __-Almost all objects expand when heated and contract when cooled. (Important Exception = WATER)__

~Celsius Scale -sets the freezing point of water at 0 degrees Celsius and the boiling point of water at 100 degrees Celsius. __-The difference between the Celsius scale and the Kelvin scale is 273. I'm not giving you the Fahrenheit conversion because we don't use Fahrenheit in chemistry__

~Kelvin Scale -sets the freezing point of water at 273.15 K and the boiling point of water at 373.15 K. __-The difference between the Kelvin and the Celsius scales are 273.__

~Absolute Zero -is the zero point on the Kelvin scale (0 K) and is equal to -273.15 degrees Celsius.

~Energy -is the capacity to do work or to produce heat.

~Joule (J) -is the SI unit of energy. __-1 J = 0.2390 cal__

~Calorie (cal) -is the quantity of heat that raises the temperature of 1 g of pure water by 1 degree Celsius. __-1 cal = 4.184 J__

__IV. Video__ media type="youtube" key="JreUzmAf8qU?fs=1" height="385" width="480"

V. Links __[|Temperature converter]__ __[|Customary to Metric Converter]__


 * Section 3.3 Conversion Factors-** __Mike McShane and Marion Burdick__

__By: Marion Burdick__ __**//Conversion Factors//**__ > ex. 1 day = 24 hours = 1440 minutes = 86400 seconds > ex. 1m/ 1m = 100m/ 1m = 1 Conversion Factor a ratio of equivalent measurements or two quantities that are equal to one another -100cm/1 m and 1m/ 100cm is an example of a conversion factor - the measurement of the numerator (the quantity on top) is equivalent to the denominator (on the bottom) -write it: so that the unit of a given measurement cancels leaving the correct unit for the answer - read: 100 cm per 1 meter (the division bar= per) Don't get it? Here's another way to look at it...
 * most quantities can be expressed in several different ways
 * when two measurements are equivalent, a ratio of the two measurements equals one (//unity//)

smaller number --> 1 m __<-- Larger unit__ __larger number --> 100 cm <-- smaller unit__ __KEY: --> is a pathetic looking arrow__

__Why use it? To solve problem in which a given measurement must be expressed in some other unit of measurement__ __Key Concept: When a measurement is multiplied by a conversion factor, the numerical value is generally changed, but the actual size of the quantity measured remains the same.__ __- conversion factors within a system of measurement are defined quantities or exact quantities and therefore have an INFINITE NUMBER of significant digits__ __Examples of conversion factors:__ 1000g __and__ 1 kg

1 kg --- 1000g 12 in. __and__ 1 ft. __1 ft. --- 12 in.__ __//**Dimensional Analysis**//__

Dimensional Analysis a way to analyze and solve problems using units, or dimensions, of the measurements Key Concept: Dimensional Analysis provides you with an alternative approach to problem solving. When doing problems follow the 3 step process of 1. Listing the knowns and the unknowns 2. Solve for the unknowns. 3. Check to see if the answer makes sense. //Converting Between Units// __Key Concept: Problems in which a measurement with one unit is converted to an equivalent measurement with another unit are easily solved using dimensional analysis.__ __//**Multistep Problems**//- Break them down by doing more than one conversion factor__ __//**Converting Complex Units-**// when measurements are expressed as a ratio of two units__ __ex. miles/hour or grams/cm or miles/gallon__ media type="youtube" key="bShwhZrEc9U?fs=1" height="385" width="640" Section 3.4 Density- Nick Brault and Elizabeth Sieber By: Nick Brault -Density is the ratio of mass (weight) to volume (space) of an object. -Density= Mass/Volume -Density depends on the makeup of an object, not its size.
 * Determining Density**

-A balloon filled with helium rises because helium is less dense than air. -Oil floats on water because water is denser than oil. -You float better in salt water than fresh water because the salt makes the water denser.
 * Real-Life Examples:**


 * Chart of Common Materials' Densities**

Chart information from:http://www.nyu.edu/pages/mathmol/modules/water/dpart3.html
 * Material || Density(G/cm^3) ||
 * Air || 0.0013 ||
 * Wood (oak) || 0.85 ||
 * Water || 1.00 ||
 * Ice || 0.93 ||
 * Aluminum || 2.7 ||
 * Lead || 11.3 ||
 * Gold || 19.3 ||
 * Ethanol || 0.94 ||
 * Methanol || 0.79 ||

By: Elizabeth Sieber //**Density and Temperature**// · When temperature changes, the volume usually does so too. · When temperature changes, the mass remains the same. · Since the volume changes, yet the mass does not, the density still changes along with the temperature***usually, as the temperature decreases, the density increases*** Calculating Density: density = mass / volume mass = 3.1 grams volume = 0.35 cm^3 density = 3.1 / 0.35 = 8.86 g/cm^3
 * //Sample Problems for Density//**
 * divide the mass (3.1 g in this case) by the volume (0.35 cm^3 in this case)

Calculating Mass (Using Density): volume = 14.8 g density = 2.34 g/cm^3 d= m/v __dv=m__ __Mass = density x volume__ __mass = 14.8 x 2.34 = 34.632__
 * to find the equation for mass, solve the density equation for m
 * v *v __multiply both sides by v__

(you could also use dimensional analysis, but I find this way easier) Calculating Volume (Using Density) __mass = 14 g__ __density = 10.5 g/cm^3__ d= m/v __dv=m__ /d /d__ divide both sides by d v = m/d Volume = Mass / Density volume = 14 / 10.5 = 1.33 cm^3 (you could also use dimensional analysis, but I find this way easier)
 * to find the equation for volume, solve the density equation for v
 * v *v __multiply both sides by v__