Question

explain how the rate of evaporation of a liquid is affected with increase in moisture in surrounding air​

Answer 1

Increase in moisture means that air also contains small particles of water(in form of vapour) in with other particles too.

We know during evaporation the water molecules get converted from liquid to gas and it goes in the air and starts filling up the space between the molecules of gas in air.

And when the spaces get filled up with the vapour condensation takes place.

Now in humid/moistorous environment the spaces between the molecules of air are already filled with vapour ( gaseous form of water). Hence this slows down the process of evaporation and the rate of evaporation is decreased.