Question

(6) A mixture of 40.0 g of oxygen and 40.0 g of helium has a total pressure of 0.900 atm.

Answer 1

Answer:

Partial pressure of oxygen  $= 0.100$ atm

Partial pressure of Helium  $= 0.800$ atm

Explanation:

We will first find the number of moles of each gas

The molar mass of oxygen is $32$ grams per mole

The molar mass of helium is $4$ grams per mole

The number of moles of oxygen in the solution

$\frac{40}{32} \\1.25$

The number of moles of helium in the solution

The number of moles of oxygen in the solution

$\frac{40}{4}\\10$

Total number of moles in the solution is equal to

$10 + 1.25 \\11.25$

Partial pressure of oxygen

$\frac{1.25 }{11.25} * 0.900$ atm

$= 0.100$ atm

Partial pressure of Helium

$\frac{10 }{11.25} * 0.900$ atm

$= 0.800$ atm