Question

Calculate the total pressure in a mixture of 8 g of dioxygen and 4 g of dihydrogen confined in a vessel of 1 dm³ at 27°C. R = 0.083 bar dm³ K^–1 mol^–1.

Answer 1

Given,

Mass of dioxygen (O₂) = 8 g

Thus, number of moles of `"O"_2 = 8/32 = 0.25` mole

Mass of dihydrogen (H₂) = 4 g

Thus, number of moles of `"H"_2 = 4/2 = 2 " mole"`

Therefore, total number of moles in the mixture

= 0.25 + 2 = 2.25 mole

Given,

V = 1 dm³

n = 2.25 mol

R = 0.083 bar dm³ K^–1 mol^–1

T = 27°C = 300 K

Total pressure (p) can be calculated as:

pV = nRT

`=> "p" = ("nRT")/"V"`

`= (225xx0.083 xx 300)/1`

= 56.025 bar

Hence, the total pressure of the mixture is 56.025 bar.