Answer to Question #156184 in General Chemistry for Aldrin

Question

The rate of effusion of Argon was measured to be 0.218 mol/s at a certain 

temperature. Calculate the rate of effusion for Helium. 

Answer 1

We know that the rate of effusion and the molar mass of the gas related as

r∝(1/molar mass,M)

So,. r2/r1 = M1/M2

Or, r2 = r1×(M1/M2)____(1)

The rate of effusion of Argon,

r1 = 0.218 mol/s

Molar mass of argon, M1 = 49 g/mol

Let the rate of effusion of helium,

r2 = x mol/s

Molar mass of helium, M2 = 4 g/mol

Putting in the equation (1) we get

r2 = 0.218×(49/4)

= 2.6705 mol/s

Hence, rate of effusion of helium = 2.6705 mol/s