A sample of gas is prepared by mixing 0.10 mol Ar, 0.10 mol N₂, and 0.30 mol He. If the entire vessel is at a pressure of 2.1 atm, what is the partial pressure of He?

Question

Quizplus · Accepted Answer

The total number of moles of gas is 0.10 + 0.10 + 0.30 = 0.50 mol. 
The partial pressure of He can be calculated using the formula:

partial pressure of He = (moles of He / total moles of gas) x total pressure

Substituting the given values:

partial pressure of He = (0.30 / 0.50) x 2.1 atm 
partial pressure of He = 1.26 atm

Therefore, the closest option is B) 1.3 atm.

A Sample of Gas Is Prepared by Mixing 0