Question

why hydrogen is collected by the downward displacement of water and not of air, even though it is lighter than air

Answer 1

This works well for hydrogen and ammonia, which are both less dense than air. Sometimes gases arecollected over water. The gas produced in a reaction is bubbled through a trough of water and into an upturned gas jar filled withwater.Nov 26, 2014

Answer 2

because highly solube in water