2. 1 Data

3. 2 SI Units: Le Systeme Internationale kilogram mass second time meter distance candela brightness mole amount Ampere current Kelvin temperature 1. Units 1.Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error Our goals

4. 3 Close your notebooks Candela (cd)Luminous intensity Ampere (A)Electric current Mole (mol)Amount of substance Kelvin (K)Temperature Kilogram (kg)Mass Meter (m)Length Second (s)Time Unit (abbreviation)Quantity 1.Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

5. 4 Giga Billion (10 9 ) 1 Mega Million (10 6 ) Thousand (10 3 ) Kilo centi Hundredth 10 -2 milli Thousandth (10 -3 ) micro Millionth (10 -6 ) nanoBillionth (10 -9 ) 2. Prefixes

6. 5 3 Derived Units Speed Meters per second m/s Density g/mL Mass/volume Volume cm 3 1 cm 3 = 1 mL Our first formula 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

7. 6 13.5 g of aluminum has a volume of 5 mL. Density? Activity: measure the density of a block of wood using 2 different methods 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

8. 7 What is the mass of 2 mL of aluminum? d =m/v v = 2 mL Density = 2.7 g/mL Must rearrange formula… m dv divide multiply m = vd = (2 mL)(2.7 g/mL) = 5.4 g 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

9. 8 Kelvin (our second formula) Temp scale that cannot go below zero 25 o C = ?K K = o C +273 = 298 K Density and temp worksheets 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

10. 9 Scientific Notation: for big and small numbers 10,000. = 1 X 10 4 Always 1-10 Always 10 x Draw a line to make it between 1 and 10 200. = 2.00 x 10 2 210. = 2.10 x 10 2 0.0009742= 9.742 x 10 -4 318.746= 3.18746 x 10 2 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

11. 10 Scientific Notation on your calculators: Use your EE button (or be sure to use parentheses) To Enter 6.02 x 10 23 type 6.02 EE 23 What is (2 x 10 1 )(1 x 10 1 )? 200 or 2 x 10 2; your calc. may say 2E2 Try this: (3 x 10 -2 ) x (-4.2 x 10 -4 ) = ? Enter 3 EE (-) 2 x (-) 4.2 EE (-) 4 = = -1.26 x 10 -5 or -0.0000126 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

12. 11 -7 x 10 -9 5.3505 x 10 3 5.84 x 10 -13 2.904 x 10 23 Try these: Scientific notation ws 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error L2 return to light unit herehere

13. 12 5. Unit Conversions A Sample Problem You have $7.25 in your pocket in quarters. How many quarters do you have? X = ___ quarters 1. Start with What you are given 3. Multiply using Conversion factors To get there 2. Write the units you need to Get to Cancel your units to prove you did it correctly. 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error 7.25 dollars 4 quarters dollar 29

14. 13 Unit Conversions Another Sample Problem Convert 65 miles/hour to meters per second 1. Start with What you are given 3. Multiply using Conversion factors To get there 2. Write the units you need to Get to Cancel your units to prove you did it correctly. (1609 meters = 1 mile; 3600 seconds = 1 hour 65 miles hour x 1 mile 1609 meters x 1 hour 3600 seconds = _____meters/second Unit conversion ws 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error 29.05

15. 14 1. When measuring include the known digits plus one estimated digit. 6. Significant Figures (L1 only): which numbers matter. What is 3/7…. 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error Volume? 32.0 mL

16. 15 Counting Significant Figures Guess which zero’s matter (L1 only) # SIG. FIGS: number why 322 1. “non-zero numbers are always significant” 0.03233 2. “leading zeroes are Never significant” 3.004 4 3. “sandwiched zeroes are always significant” 300 1 4. “trailing zeroes are only significant if there is a decimal place” 300.3 300.20 5 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

17. 16 Learning Check A. Which 2 answers contain 3 significant figures? 1) 0.4760 2) 0.00476 3) 4760 B. All the zeros are significant in 1) 0.00307 2) 25.300 3) 2.050 x 10 3 C. 534,675 rounded to 3 significant figures is 1) 535 2) 535,000 3) 5.35 x 10 5 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error

18. 17 7. Percent Error You measure your mass to be 120 lbs, but in reality it is 150 lbs. What is your percent error? = 30 lbs/150 lbs x 100 = 20% End data unit 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error