Chem Unit 1: Measurements

Metric prefix symbol: P

Peta, 10^15

Metric prefix symbol: T

Tera, 10^12

Metric prefix symbol: G

Giga, 10^9

Metric prefix symbol: M

Mega, 10^6

Metric prefix symbol: k

kilo, 10³

Metric prefix symbol: h

hecto, 10²

Metric prefix symbol: da

deca, 10^1

Metric prefix symbol: d

deci, 10^-1

Metric prefix symbol: c

centi, 10^-2

Metric prefix symbol: m

milli, 10^-3

Metric prefix symbol: μ

micro, 10^-6

Metric prefix symbol: n

nano, 10^-9

Metric prefix symbol: p

pico, 10^-12

Example problem: 1 Mm = __ m

10^6 m (remember that the multiplier always goes with the base unit)

Sig Figs (short for significant figures) rules, 5 in total

1. Every nonzero digit in a recorded measurement is significant (ex. 47,357 has 5 sig figs)

2. Zeroes appearing between nonzero digits are significant (sandwich rule; ex. 1.007 has 4 sig figs)

3. Zeroes appearing in front of all nonzero digits are not significant and are acting as placeholders (leading zeroes; ex. 0.00237 has 3 sig figs)

4. Zeroes at the end of a number and to the right of a significant digit are significant (ex. 426.00 has 5 sig figs)

5. Zeroes at the end of a measurement where there is no decimal point are ambiguous. To clearly show correct number of sig figs these measurements should be written in scientific notation (ex. 120 has 2-3 sig figs and 3000 has 1-4 sig figs; decimal point makes the measurement significant. for example 120.00 has exactly 5 sig figs, not 3-5)