Question

A neon-dioxygen mixture contains $70.6g$ dioxygen and $167.5g$ neon. If the pressure of the mixture of gases in the cylinder is $25$ bar. What is the partial pressure of dioxygen and neon in the mixture?

Answer 1

The mass of dioxygen is 70.6 g.

The molar mass of dioxygen is 32 g/mol.

The number of moles of dioxygen

$=\frac{\text{70.6 g}}{\text{32 g/mol}}=\text{2.21 mol}$

The mass of neon is 167.5 g.

The molar mass of neon is 20.2 g/mol.

The number of moles of neon

$=\frac{\text{167.5 g}}{\text{20.2 g/mol}}=\text{8.29 mol}$

The total number of moles of neon and dioxygen $=\text{2.21}+\text{8.29}=\text{10.49}$

The mole fraction of neon $=\frac{\text{8.29}}{\text{10.49}}=\text{0.789}$

Total pressure in the cylinder is 25 bar.

The partial pressure of neon $=\text{0.789}\times \text{25 bar}=\text{19.7 bar}$

The partial pressure of dioxygen $=\text{25 bar}-\text{19.7 bar}=\text{5.3 bar}$