This document covers key concepts in scientific measurement including: 1. The seven SI base units including meters, kilograms, seconds, etc. 2. Common unit prefixes like milli, centi, and kilo and their abbreviations. 3. Temperature scales including Kelvin and conversions between Celsius, Fahrenheit and Kelvin. 4. Scientific notation for writing very large and small numbers. 5. Converting between units using conversion factors and canceling units. 6. Rules for determining significant figures and counting zeros. 7. Calculating percent error in measurements.

1. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorSI Units: Le SystemeInternationaleUnit 2: DataIdentify the 7 common SI units:KelvintemperatureAmperekcurrentsecondstimeAmolemeteramountmolmdistancecandelabrightnesscdkgkilogrammassCombined Units:speedaccelerationdensityvolumeDensity formula:1

2. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorUnit 2: DataDensity calculations13.5 g of aluminum has a volume of 5 mL. Density?What is the mass of 2 mL of aluminum?m = vd

3. = (2 mL)(2.7 g/mL)

4. = 5.4 gdividemmultiplydv2

5. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorUnit 2: DataBillion (109)Giga (G)2. PrefixesMega (M)Million (106)List the common unit prefixes and their abbreviationskilo (k)Thousand (103)learn more1Hundredth 10-2centi (c)milli (m)Thousandth (10-3)micro (m)Millionth (10-6)3nano (n)Billionth (10-9)

6. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorTemperatureUnit 2: DataWhen is Kelvin normally used and why?KelvinTemp scale that cannot go below zero:K to 0C:25oC = ?KK = oC +273= 298 KIn many formulas: it is mathematically accurate.0F to 0C:°C= (°F - 32) × 5/9°F = ° C× 9/5 + 32 -40oC = ?0Fx9 = -360, /5 = -72, + 32 = -40 0F -40oF = ?0C-32 = -72, x5 = -360, /9 = -40 = -40 0C 44

7. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorScientific Notationfor big and small numbersExample:Try some:= 2.12 x 102212.009710,000= 9.7x 10-3= 1 x 104602,000,000,000,000,000,000,000Draw a line to make it between 1 and 10; count to decimal point.Always 10xAlways 1-10= 6.02x 1023-2860= -2.86 x 103= 9.742 x 10-4.00097425

8. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorScientific Notation on your calculators: 2 methodsEnter 6.02 x 1023For fancy calculators (like TI-83, etc)For cheaper calculators that don’t do ()Enter it all in parentheses- you’ll need themUse EE button, no parentheses neededEnter (6.02x10^23)Enter 6.02E23Example: what is (2 x 101)(1 x 101)?Enter (2 x 10^1)(1 x 10^1)Enter 2E1x1E1= 200 or 2E2Try this: (3 x 10-2) x (-4.2 x 10-4) = ?Enter (3x10^-2)x(-4.2x10^-4)Enter 3E-2x-4.2E-4Negative, not subtractNegative, not subtractAdd answer= -1.26 x 10-5 or -0.00001266

9. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error5. ConversionsA Sample ProblemYou have $7.25 in your pocket in quarters. How many quarters do you have?1. Start withWhat you aregiven3. Multiply usingConversion factorsTo get there2. Write the units you need toGet to4 quarters29= ___ quartersX7.25 dollarsdollarCancel your units to prove you did it correctly.7

10. 1. Units 2. Prefixes 3. Dens./temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorData: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorConvert 65 miles/hour to meters per second(1609 meters = 1 mile; 3600 seconds = 1 hour1. Start withWhat you aregiven3. Multiply usingConversion factorsTo get there2. Write the units you need toGet to1609 meters1 hour65 milesxxmeterssecond= 29.05hour1 mile3600 secondsCancel your units to prove you did it correctly.Slightly Harder Conversions8

11. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % error6. Significant Figures1. When measuring include the known digits plus one estimated digit.Volume?32.0 mL9

12. Data: 1.Units2. Prefixes 3. temp. 4. Sci. not. 5. Conversions 6. sig. fig.’s 7. % errorSignificant Figures: Guess which zero’s matter (L1 only)numberwhy# SIG. FIGS:1. “non-zero numbers are always significant”3222. “leading zeroes are Never significant”0.032333. “sandwiched zeroes are always significant”3.004430014. “trailing zeroes are only significant if there is a decimal place”300.35300.20.030690Summary:Keep if decimal presentdump10keep