Under certain conditions argon (ar) gas diffuses at a rate of 3.2 centimeters per second. under the same conditions, an unknown gas diffuses at a rate of 4.5 centimeters per second. what is the approximate molar mass of the unknown gas?

a) 10 g/mol
b) 20 g/mol
c) 28 g/mol
d) 56 g/mol

c) 28 g/mol

Explanation: Rate of diffusion : It is defined as the volume of gas effused in a given time 't'.

Formula used :

According to Graham's law of diffusion, rate of diffusion is inversely proportional to the square root of the mass of the gas.

where,

= rate of diffusion of argon gas = 3.2cm/sec

= rate of diffusion of unknown gas = 4.5 cm/sec

= Molar mass  of argon gas= 40g/mol

=  Molar mass  of unknown gas