JAMB - Chemistry (1988 - No. 37)
The molar ratio of oxygen to nitrogen in dissolved air is 2:1 whereas the ratio is 4:1 in atmospheric air because?
nitrogen is less soluble than oxygen
oxygen is heavier than nitrogen
nitrogen has a higher partial pressure in air
gases are hydrated in water
Explanation
the ratio of oxygen to nitrogen in dissolved air is 2:1 whereas the ratio is 4:1 in atmospheric air. This is because oxygen in the air has a higher solubility than other elements in the air and also there is hydrogen bonding between water and oxygen that increases its solubility.