Question

A heliox deep-sea diving mixture contains 2.0 gg of oxygen to every 98.0 gg of helium. What is the partial pressure of oxygen when this mixture is delivered at a total pressure of 8.0 atm?

Answer 1

Answer:

The correct answer is 0.020 atm.

Explanation:

Partial pressure is calculated by using the formula,

Partial pressure = Mole fraction × Total pressure

The partial pressure of oxygen in a mixture can be calculated by using the formula,  

Mole fraction of oxygen in mixture = Number of moles of oxygen / No. of moles of oxygen + No. of moles of Helium

(1 gg or gigagram is equal to 10⁹ grams)

= 2 × 10⁹/32 /2 × 10⁹/32 + 98 × 10⁹ / 4

= 2.54 × 10⁻³

Now the partial pressure of oxygen = Mole fraction of oxygen × Total pressure of oxygen

= 2.54 × 10⁻³ × 8.0 atm

= 0.02032 atm

= 0.020 atm