Final answer:
Using Graham's law of effusion, the molecular weight of a gas that diffuses 1/5 times as fast as hydrogen is found to be 50.0 g/mol.
Step-by-step explanation:
The student's question involves finding the molecular weight of a gas that diffuses 1/5 times as fast as hydrogen. We can use Graham's law of effusion to solve this problem:
Graham's law states that the rate of effusion of a gas is inversely proportional to the square root of its molar mass. Mathematically, this can be represented as:
Rate of effusion of Gas 1 / Rate of effusion of Gas 2 = sqrt(Molar mass of Gas 2 / Molar mass of Gas 1)
If the unknown gas diffuses 1/5 as fast as hydrogen, and the molar mass of hydrogen (¹H₂) is 2.0 g/mol, then:
(1/5) = sqrt(Molar mass of unknown gas / 2.0 g/mol)
Squaring both sides, we get:
(1/25) = Molar mass of unknown gas / 2.0 g/mol
Thus, the molar mass of the unknown gas is 2.0 g/mol × 25, which equals to 50.0 g/mol.
Therefore, the molecular weight of the gas that diffuses 1/5 times as fast as hydrogen is 50.0 g/mol.