2.  Chemistry is the study of the composition of matter and the changes that matter undergoes  What is matter?  Matter is anything that has mass and occupies space (volume)  Everything is made up of matter!!

3.  Chemistry is needed to  Explain the natural world  Prepare for a career  Be an informed citizen  Chemistry is used to  Conserve, produce, and store energy  Develop medicines, material, and technologies for medical treatment  Develop productive crops  Identify and prevent pollution  Understand the universe

5.  All of the digits in a measurement that are known, plus a last digit that is estimated  Used in science to increase accuracy and certainty of data

6.  Atlantic/Pacific Rule

7.  Atlantic Rule  If a decimal is absent, start from Atlantic side (right) till you reach the first non-zero digit  Every digit from thereafter is significant (including any zeros)  387,000  200  400,300

8.  Pacific Rule  If a decimal is present, start from the Pacific side (left) until you reach the first non-zero digit  Every digit from there after is significant (including any zeros)  0.013  0.0010778  4.00

9.  How many significant figures?  0.0004809  34,980,000  483,082,000,000  0.00000038  5,600  1.030  4,009

10.  Determine the amount of significant figures (Atlantic/Pacific rule) that each number from the problem has  Calculate as normal  Rule:  Express your answer by rounding to the same number of sig figs as the number with the least sig figs from the problem

11. 1) 4040 x 21 (3) (2) = 84,840 = 85,000 2) 98.0 /.8775 =111.6809 = 112 3) 0.017 x 103 x 2.8 = 4.9028 =4.9

12.  Calculate as normal  Rule:  Express your answer by rounding to the same number of decimal places as the measurement with the least number of decimal places from the problem

13. 1) 40.108 2.3 + 6821.4001 6863.8081 = 6863.8 2) 42.9 – 18.01 = 24.89 = 24.9 3) 125.25 + 46.02 - 86.257 =85.013 = 85.01

14.  Solve the following problems, express your answer using the correct number of significant figures