# What is the equation of the ideal gas law?

May 27, 2014

The equation is PV = nRT?

Where the pressure - P, is in atmospheres (atm) the volume - V, is in liters (L) the moles -n, are in moles (m) and Temperature -T is in Kelvin (K) as in all gas law calculations.

When we do the algebraic reconfiguration we end up with Pressure and Volume being decided by moles and Temperature, giving us a combined unit of
$\frac{a t m x L}{m o l x K}$. the constant value then becomes 0.0821 $\frac{a t m \left(L\right)}{m o l \left(K\right)}$

If you choose not to have your students work in standard pressure unit factor, you may also use: 8.31 $\frac{k P a \left(L\right)}{m o l \left(K\right)}$ or 62.4 $\frac{T \mathmr{and} r \left(L\right)}{m o l \left(K\right)}$.

Temperature must always be in Kelvin (K) to avoid using 0 C and getting no solution when students divide.

There is a variation of the ideal gas law that uses the density of the gas with the equation PM = dRT

Where M is the Molar Mass in $\frac{g}{m} o l$ and d is the Density of the gas in $\frac{g}{L}$.

Pressure and Temperature must remain in the units atm and K and the Gas Law Constant remains R = 0.0821 $\frac{\left(a t m\right) L}{\left(m o l\right) K}$.