The rate of effusion of H₂ : 7.2 x 10⁻² m/s
Further explanation
Graham's law: the rate of effusion of a gas is inversely proportional to the square root of its molar masses or
the effusion rates of two gases = the square root of the inverse of their molar masses:
or
MW₁ O₂ = 32 g/mol
MW₂ H₂ = 2 g/mol