Answer:
Molar mass = 71.76 g/mol
Explanation:
The relationship between molar mass and rate of effusion is given as;
Vh / Vu = √ (Mu / Mh)
The rate of effusion of a gas is inversely proportional to the square root of the mass of its particles.
Rate = volume / time (Assuming Volume = 1)
Vh = Rate of effusion of Hydrogen = 1 / 2.42
Vu = Rate of effusion of unknown gas = 1 / 14.5
Mh = Molar mass of hydrogen = 2
Mu = Molar mass of unknown gas = x
Substituting into the formular, we have;
(1 / 2.42) / (1 / 14.5) = √ ( x / 2)
5.99 = √ ( x / 2)
35.88 = x / 2
x = 71.76
