Answer : The ratio of effusion rates for helium and argon is 3.2 : 1
Solution : Given,
Molar mass of Helium = 4 g/mole
Molar mass of Argon = 40 g/mole
Rate of effusion : It is defined as the rate of effusion of a gas is inversely proportional to the square root of the molar mass of the gas.
Formula used :
[tex]\text{Rate of effusion}=\frac{1}{\sqrt{M}}[/tex]
where, M is the molar mass.
[tex]\frac{Rate_{He}}{Rate_{Ar}}=\sqrt{\frac{M_{Ar}}{M_{He}}}[/tex]
Now put all the given values in this expression, we get
[tex]\frac{Rate_{He}}{Rate_{Ar}}=\sqrt{\frac{40}{4}}=\frac{3.2}{1}[/tex]
Therefore, the ratio of effusion rates for helium and argon is 3.2 : 1
