Question

PLEASE HELP!!!

Answer 1

Answer: The molar mass of the unknown gas is 118.26 g/mol.

Explanation:

Graham's law: The rate of diffusion of gaseous substance in inversely proportional to the  square root of its molecular mass.

$R_g\propto \frac{1}{\sqrt{M_g}}$

Rate of the unknown gas ,R=R

Rate of the HCl gas,R' = 1.8R

Molar mass of unknown gas = M

Molar mass of the HCl gas = 36.5 g/mol

According to Graham's law:

$\frac{R}{R'}=\frac{R}{1.8R}=\sqrt{\frac{36.5 g/mol}{M}}$

$(\frac{1}{1.8})^2=\frac{36.5 g/mol}{M}$

$M=1.8\times 1.8\times 36.5 g/mol=118.26 g/mol$

The molar mass of the unknown gas is 118.26 g/mol.