On a certain humid day, the mole fraction of water vapour in air at `25^(@)C` is 0.0287. If total pressure of air is 0.977 bar, calculate the partial pressure of water vapour in air and relative humidity if vapour pressure of water at `25^(@)C` is 0.0313 bar.

Explanation

Here, `x_(H_(2)O)=0.0287, P_("total")=0.977" abr"`
`p_(H_(2)O)=x_(H_(2)O)xxP_("total")=0.0287xx0.977" bar "=0.028" bar"`
% Relative humidity`=(p_(H_(2)O)" in air")/("Vapour pressure" of H_(2)O)xx100=(0.028)/(0.0313)xx100=89.4%`.