Question

A vessel contains a mixture of nitrogen (m₁ = 7.0 g) and carbon dioxide (m₂ = 11 g) at a temperature T = 290 K and pressure p₀ = 1.0 atm. Find the density of this mixture, assuming the gases to be ideal.

Answer 1

We know, for the mixture, N₂ and CO₂ (being regarded as ideal gasses, their mixture too  behaves like an ideal gas)

pV = vRT, so p₀V = vRT

where, v is the total number of moles of the gases (mixture) present and V is the volume of the vessel. If  v₁ and v₂ are number of moles of N₂ and CO₂ respectively present in the mixture, then 

v = v₁ + v₂

Now number of moles of N₂ and CO₂ is, by definition given by