Standing at the top of a tall mountain,a breath of air would contain a lot fewer molecules than a breath of air taken at sea level.But the proportion of oxygen in the two breaths of air,relative to the other constituents,would remain the same.

Question

Quizplus · Accepted Answer

The proportion of oxygen in the air remains the same regardless of altitude, so the statement is true. However, the total pressure of the air decreases with altitude, leading to a lower concentration of all gases in the breath taken at the top of the mountain.

Standing at the Top of a Tall Mountain,a Breath of Air