Question

The rate of diffusion of an unknown gas is 1.73 times smaller than rate of diffusion of oxygen. Find molar mass of unknown gas.


please i cannot understand this question can anyone give me a detailed explanation​

Answer 1

Given - Rate of diffusion of unknown gas - 1.73 times less than rate of diffusion of oxygen.

Find - Molar mass of unknown gas.

Solution - Molar mass of unknown gas can be calculated by the help of Graham's law of diffusion. As per the law, rate of diffusion is inversely proportional to square root of molecular weight.

Let the rate of diffusion of unknown gas be X. Therefore, rate of diffusion of oxygen will be 1.73 times the rate of diffusion of unknown gas and hence can be written as 1.73x.

Keeping the values in formula -

R1/R2 = ✓(M2/M1)

X/1.73X = ✓(32/M1)

32/M1 = 1/1.73²

32/M1 = 1/3

M1 = 32*3

M1 = 96 gram/mol.

Hence, the molar mass of unknown gas is 96 gram/mol.