Question #95169

1 Answer
Jul 25, 2016

The relative molecular mass of gas Z is 32

To get feasible result the volume of hydrogen gas diffused is considered #200cm^3#.

Explanation:

To solve this problem we are to apply Graham's law of diffusion which states that the rate of effusion or of diffusion (R)of a gas is inversely proportional to the square root of its molecular weight or relatve molecular mass (M) at constant temperature and pressure.

#color(red)("Symbolically, "R prop 1/sqrtM)#

Let

#M_Z->"Relative molecular mass of gas Z"=?#

#M_H->"Rel. molecular mass of Hydrogen"=2#

#R_Z->"Rate diffusion of gas Z"=100/10=10"cm"^3/s#

#R_H->"Rate diffusion of Hydrogen"=200/5=40"cm"^3/s#

Now by Graham's law

#R_H/R_Z=sqrt(M_Z/M_H)#

#=>40/10=sqrt(M_Z/2)#

#M_Z=4^2*2=32#

The relative molecular mass of gas Z is 32