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The ideal gas law

The ideal gas law connects pressure, volume, amount of substance and temperature for a gas. It holds well for most gases at ordinary pressure and temperature. The temperature must always be in kelvin.

pV = nRT

ideal gas law

R = 8.314\ \tfrac{J}{mol\cdot K}

gas constant

Symbols

$p$	pressure	Pa
$V$	volume	m³
$n$	amount of substance	mol
$T$	temperature	K

Example

1 mol of gas at 0 °C and 101.3 kPa:

$V = nRT/p = 8.314\cdot 273/101\,300 \approx 0.0224$ m³ = 22.4 L.

Convert to SI units first: Pa, m³ and K.

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Part of General Chemistry: Gas laws.