Problem: Gas Y effuses half as fast as O2. What is the molar mass of gas Y?

FREE Expert Solution

We’re being asked to calculate molar mass of gas Y if it effuses half as fast as O2.


Recall that Graham's Law of Effusion allows us to compare the rate of effusion of two gases. Graham's Law states that the rate of effusion of a gas is inversely proportional to its molar mass.


rate=1MMgas


This means that when comparing two gases:


rategas 1rategas 2=MMgas 2MMgas 1


Let's designate O2 as gas 2 and the gas Y as gas 1


rate gas Y = 0.5 (rate O2)

  • rategas 1rategas 2=0.5


The molar mass of O2 is:

O2       2 O × 16 g/mol O = 32 g/mol     

                               Sum = 32 g/mol


79% (124 ratings)
View Complete Written Solution
Problem Details

Gas Y effuses half as fast as O2. What is the molar mass of gas Y?

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Effusion concept. You can view video lessons to learn Effusion. Or if you need more Effusion practice, you can also practice Effusion practice problems.