Question

Air is comprised predominantly of nitrogen (N2) and oxygen gas. The ambient air in this room contains about 0.28g of oxygen (O2) gas per liter of air. A typical human at rest inhales about 19.3 fluid ounces (fl.oz.) of air per breath. And at rest takes about 20 breaths per minute. How many grams of oxygen gas does a human at rest inhale in an hour? Show all calculations with the correct units for full credit.

Answer 1

190 g

Step-by-step explanation:

Knowing that:

• O₂ gas in air: 0.28 g O₂ / L of air
• Air inhaled at rest: 19.3 fl.oz. air / breath
• Human takes 20 breaths / min

The grams of oxygen gas (O₂) that a human at rest inhales in 1 hour (60 minutes) will be calculated as:

grams of O₂ = breaths in 1 hour * air inhaled per breath * amount of O₂ in air

`grams O_(2) = 60 min* 20 (breath)/(min) * 19.3 (fl.oz. air)/(breath) * (1 L)/(33.814 fl.oz.) * 0.28 (g O_(2) )/(L)`

grams of O₂ = 191.78 g

190 g of O₂ are inhaled in 1 hour (written in correct number of significant figures)

*In the calculation the amount of air inhaled per breath was converted from fl.oz. to Liters knowing that 1 L = 33.814 fl.oz.