1. UNIT 1 INTRODUCTION AND MEASUREMENT
What is Chemistry?
How can problems be solved in a systematic manner?
How do we give meaning and dimension to our descriptions of the world around us?
How can units be used to solve problems?
How do we perform simple calculations during experiments?

2. AIM # 1: What is Chemistry?
DO NOW: Answer the following questions
What is Chemistry?
-is the study of the composition of substances and the changes they undergo
- science of matter, an interaction between atoms

3. AIM: What is Chemistry?
2. What are the four main divisions of chemistry?
Organic chemistry: the study of substances that contain carbon
Example: How gasoline is produces from oil
Inorganic chemistry: the study of substances without carbon
Example: how table salt reacts with different acids
Analytical chemistry: the study of the quantitative composition of substances
Examples: how much chlorine is in a sample of tap water
Biochemistry: the study of chemistry of living organisms
Examples: how sugar in the blood stream of cats affect insulin production

5. AIM: What is Chemistry? - everyday examples (you do not have to write this down!!!!)
Digestion; enzymes promoting chemical reactions that power our bodies. Lifting your arm requires your body to make and burn ATP using oxygen with carbon dioxide as one of the waste gases produced.
Cooking is the heating and combination of compounds to make something new. In some cases, like rising bread we have an actual chemical reaction where the yeast changes the food.
When concrete dries and hardens the water actually causes a chemical reaction with the cement making a binding action drying concrete isn't just losing water it is undergoing a chemical change and one that creates heat as well (an exothermic reaction).

6. AIM: What is Chemistry? - everyday examples
4. When you write with ink on paper, the ink and paper unite in a chemical reaction so that you can't erase it. Specialized inks allow a short period where you can erase some inks, but most inks dry and can't be erased; they have bound with the paper. This includes your pen and your ink jet printer.
5. Plastics are all about organic chemistry.
The sun undergoes fusion and yes that too is chemistry. It creates radiation and photons so we can see. Some of the radiation interacts with oxygen to create ozone and the ozone layer shields us from harmful UV radiation.
ANYTHING that burns is undergoing a chemical reaction and almost always creates some form of carbon as waste.

7. AIM# 2: How can problems be solved in a systematic manner?
The scientific method is a way to solve a scientific problem. It is an approach to a solution (using mostly common sense)

8. AIM: How can problems be solved in a systematic manner?
- Steps of the Scientific Method
Objective (Problem): statement of purpose
Hypothesis (Prediction): Educated guess, in the form: if …. then…
Experiment (Test): to test hypothesis, must give reproducible results to be reliable
Variable: factor being tested
Control: other factors that are held constant

9. AIM: How can problems be solved in a systematic manner?
- Steps of the Scientific Method
Observations (Data): collect and gather data based on your observations; organize these results to perform analysis in the form of charts, tables or graphs
Qualitative
Quantitate
5. Analysis: (Results): organizing data into meaningful groups, tables, and charts

10. 6. Conclusions: the determination if your hypothesis was correct, it may be accepted, rejected revised
7. Follow up/application: a repeat with modification is sometimes necessary, and a reevaluation of the results. Also answering one question often leads to new questions. How could you use and communicate the information of your experiment. Why is it important and who could benefit from it?

12. AIM: How can problems be solved in a systematic manner?
- Law vs. Theory
Theory: explains the results of experiments, they can change or be rejected over time because of results from new experiments Law: describes natural phenomena, it tells what happens and does not attempt to explain why the phenomena occurs (that is the purpose of a theory). Laws can often be summarized by a math equation

13. Precision and Accuracy
Accuracy- closeness of a value to the true value
Hitting the bullseye when you are aiming for it
For most experiments the accuracy means how far the deviation is from the expected value
Precision- is the closeness of measurements to each other

14. Accurate and precise- Casie
Not precise, but one piece of data is accurate- Carmen
Precise but not accurate- Cynthia
Neither precise nor accurate - Cheryl

15. AIM # 3: How can we give meaning and dimension to our description of the world around us? – Metric System
Measurement gives the universe meaning! How tall are you? How much do you weigh? How old are you? How fast can you run? How much volume do you displace? All of these questions are designed to give us reference to the world around us.

17. AIM # 3 (a): How can we give meaning and dimension to our description of the world around us? – Math Rules for Chem

19. AIM: How can we give meaning and dimension to our description of the world around us? – Sig Fig Rules
Atlantic and Pacific Rule:
If a decimal point is present (Pacific side) you start counting from left to right with the first non zero number
If a decimal point is absent (Atlantic side) you start count from right to left with the first non zero number

20. AIM: How can we give meaning and dimension to our description of the world around us? – Sig Fig Rules
Examples:
cm ________________
8000 sec ________________
40. L ______________
2300 g ________________

21. Calculating with sig figs
 Multiplication and Division: want your answer to have the same number of SIG FIGS as the measurement that has the least number of sig figs 
Examples:
x 2.25 =
cm x 1.6 cm x 2.12 cm =

22. Calculating with sig figs
Addition and Subtraction: want your answer to have the same number of DECIMAL PLACES as the measurement that has the least number of DECIMAL PLACES
Examples: =
3.842 cm cm cm =

23. - Scientific Notation

25. AIM# 3 (b): How is the data compression in mp3 and ZIP files mirrored in scientific notation? - sci notation

26. Comparing relative magnitudes of two numbers in scientific notation:

27. AIM#4: How can units be used to solve problems? - dimensional analysis
To covert a measurement from one metric unit to another, you must know the difference in magnitude between the two prefixes and use the to create a conversion factor

28. AIM: How can units be used to solve problems? - dimensional analysis
Use Reference Table C. If there is no prefix (m, g, L, etc.) then the power of ten is The prefix is underlined so you can verify its magnitude against Reference Table C. The smaller unit is italicized

29. AIM: How can units be used to solve problems? - dimensional analysis
TO USE THE CONVERSION FACTOR: **NOTES: the number of sig figs in your final answer equals the number of sig figs in the number you are converting **
Given amount multiplied or divided by the conversion = answer
If the given unit is also the numerator unit on the conversion factor, then DIVIDE to cancel it out
If the given unit is also the denominator unit on the conversion factor, then MULTIPLY to cancel it out

30. DIMENSIONAL ANALYSIS EXAMPLES

31. Ex 1) A pin measuring 2.85 cm in length. What is its length in inches?
Need an equivalence statement
2.54cm = 1in
Divide both sides by 2.54cm
Unit Factor
Multiply any expression by this unit factor and it will not change its value

32. Ex 1) A pin measuring 2.85 cm in length. What is its length in inches?

33. Ex 2) A pencil is 7.00 in long. What is the length in cm?
Convert in  cm
Need equivalence statement 2.54cm = 1in
Unit Factor

34. DIMENSIONAL ANALYSIS

35. DIMENSIONAL ANALYSIS and
How to choose – look at direction of required change
in  cm (need to cancel in – goes in denominator)
cm  in (need to cancel cm – goes in denominator)

36. Ex 3) You want to order a bicycle with a 25
Ex 3) You want to order a bicycle with a 25.5in frame, but the sizes in the catalog are given only in cm. What size should you order?

37. Ex 4) A student entered a 10.0-km run. How long is the run in miles?
km  mi
Equivalence statement 1m = 1.094yd
Strategy first
km  m  yards  mi
Equivalence statements:
1km = 1000m
1m = yd
1760yd = 1 mi

38. Ex 4) A student entered a 10.0-km run. How long is the run in miles?
km  m

39. Ex 4) A student entered a 10.0-km run. How long is the run in miles?
m  yd

40. Ex 4) A student entered a 10.0-km run. How long is the run in miles?
yd  mi
Original 10.0 which has 3 sig figs so you want 3 sig figs in your answer

41. Ex 4) A student entered a 10.0-km run. How long is the run in miles?
Can combine all conversions into one step

43. AIM # 5: How do we perform simple calculations during experiments
Percent Error- the measurement of the percent that the measured value is “off” from the accepted value
Measured value
Accepted value
Percent error % error= measured value- accepted value x 100
accepted value
(found on table T)

44. Density d = m v