Gas Laws Summary

Kelvin Scale: Use Kelvin for all gas law problems. $K = °C + 273$ . Zero Kelvin (absolute zero) means no molecular movement.
Pressure Units: Various units exist; convert as needed. $1 atm = 1.01325 \times 10^5 Pa = 101.325 kPa = 760 mmHg = 760 torr = 14.7 psi$
STP (Standard Temperature & Pressure): $0° C = 273 K$ and $1 atm = 760 mmHg$

Boyle's Law: $P1V1 = P2V2$ (Temperature and # moles held constant; Indirect/Inverse relationship)
Charles' Law: $\frac{V1}{T1} = \frac{V2}{T2}$ (Pressure and # moles held constant; Direct relationship)
Gay-Lussac's Law: $\frac{P1}{T1} = \frac{P2}{T2}$ (Volume and # moles held constant; Direct relationship)
Avogadro's Law: $\frac{V1}{n1} = \frac{V2}{n2}$ (Pressure and temperature held constant; Direct relationship)
Combined Gas Law: $\frac{P1V1}{T1} = \frac{P2V2}{T2}$ (# of moles held constant; Combines most common variables)