Question

Why is oxygen heavier than air?

Answer 1

Oxygen is denser than air.

Step-by-step explanation:

This is because oxygen gas comes from its molecular weight. Also air is mainly made up of nitrogen and nitrogen is lighter than oxygen.

Answer 2

Oxygen is denser

Step-by-step explanation:

Oxygen is denser than both air and nitrogen, at all temperatures and pressures, but only slightly. Since they don't separate from each other, we generally don't worry which is lighter or heavier. The difference in the density of nitrogen and oxygen gas comes from their molecular weight, which is small (4 g/mol)