Question

A sample consisting of various gases contains 3.2×10−6 mole fraction of radon. This gas at a total pressure of 34 atm is shaken with water at 30 ∘C. Calculate the molar concentration of radon in the water. Express your answer using two significant figures.

Answer 1

Answer:

The molar concentration of radon is 4.38 x 10⁻⁶ mol.L⁻¹

Explanation:

Molar fraction = number of moles of a certain component / total number of moles

Partial pressure = Total pressure x molar fraction

Partial pressure = 34 atm x 3.2 x 10⁻⁶

Partial pressure = 1.09 x 10⁻⁴ atm

Considering radon as an ideal gas, PV = nRT

molar concentration = n/V

n/V = P/RT

n/V = 1.09 x 10⁻⁴ atm / 0.082 L.atm.mol⁻¹K⁻¹ x 303.15K

n/V = 4.38 x 10⁻⁶ mol.L⁻¹