If oxygen effuses through an opening at a rate of 67 particles per second, how fast would effuses Hydrogen gas effuse through the same opening?

1 Answer
May 1, 2016

268 particles per second.

Explanation:

Graham's law of effusion says that

R_1/R_2=sqrt(M_2/M_1),

where R is the rate of effusion and M is the mass. The subscript number refers to either oxygen or hydrogen - it's a relative equation.

If we say that substance 1 is hydrogen and 2 is oxygen, then

R_1=?
R_2=67

M_1=1
M_2=16

(M values from the periodic table).

Putting these values into a rearranged equation,

R_1=R_2*sqrt(M_2/M_1)
R_1=67*sqrt(16/1)=67*4=268