1.2 Units, Conversions, and Significant Figures


Chad's Ultimate General Chemistry Course

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The Metric System

Metric Prefixes
Terra 1012
Giga 109
Mega 106
kilo 103
centi 10-2
milli 10-3
micro 10-6
nano 10-9
pico 10-12
femto 10-15
atto 10-18
SI Units
Length m (meter)
Mass kg (kilogram)
Time s (second)
Temperature K (Kelvin)
Electric Current A (Ampere)
Luminous Intensity Cd (candela)
Derived Units
Volume m3 (cubic meter)
Energy/Work J (Joule)
Pressure Pa (Pascal)
Force N (Newton)
Power W (Watt)
Charge C (Coulomb)
Resistance Ω (Ohm)
Capacitance F (Farad)

Significant Figures

Rules for Zeroes with Significant Figures
1) Zeroes in between significant figures are significant.
2) Zeroes at the beginning of a number are insignificant.
3a) Zeroes right of the decimal, at the end of a number are significant.
3b) Zeroes left of the decimal (not visible), at the end of a number are NOT significant.