2. Math vs. Science mathematicianto a mathematician: 73 = 73.0 = 73.00 = 73.000 etc scientistto a scientist, these numbers have a more complicated meaning

3. Numbers in Science counts counts are exact and have infinite number of significant figures there are 30 desks in this room 30 = 30. = 30.0 = 30.00 = 30.000 desks

4. significant figures are used for data calculations in chemistry because.. dealing with large numbers of very small particles – often written to power of 10 ex: (3.26 x 10 -5 )

5. How do I figure out how many Significant Figures?

6. X   X the easiest way to count sig figs is by using the Atlantic and Pacific Rule

7. to help determine how to count # of sig figs ask yourself this question: does the number have a decimal point? decimal point Absent start counting from Atlantic Ocean (right side) of # Atlantic Ocean (right side) of # decimal point Present start counting from Pacific Ocean (left side) of # Pacific Ocean (left side) of #

8. Decimal point absent: Start on Atlantic (right) side of # non-zeroStart counting with first non-zero digit & count until reach end of # 5400 m has 2 2 sig figs 5431 m has 4 4 sig figs 5400 5431

9. Decimal point present: non-zeroStart counting with first non-zero digit & count until reach end of # 2545.300 g 0.004530 km has 7 7 sig figs has 4 4 sig figs Start on Pacific (left) side of # 2545.300 0.004530

10. sometimes, after math calculations your answer may not contain enough sig figs because… there are zeros that are not considered significant answer: 5300 but need 3 sig figs

11. if you want a zero to be significant draw a line above to show that it is significant

12. BLUE MOON rule once in a BLUE MOON rule 5300 cm becomes: 5300 cm _

13. when doing calculations that involve: Multiplication and Division sig figs least number answer: only have as many sig figs as data number with least number of sig figs

14. 24.56 cm x 14 cm = 1. 343.84 cm 2 2. 343.8 cm 2 3. 343 cm 2 4. 340 cm 2 correct answer: 4 2 sig figs

15. when doing calculations that involve: Addition and Subtraction decimal placesleast number answer: only have as many decimal places as data number with least number of decimal places

16. 422.63 cm 29.472 cm 115.9 cm ________________ + a) 568.002 cm b) 568.00 cm c) 568.0 cm d) 568 cm correct answer: C 1 decimal place