What is the mass of a mole of water containing 50% of heavy water `(D_(2)O)`?

Explanation

As water contains `50%D_(2)O`, this means that it contains `(1)/(2)` mole of `H_(2)O` and `(1)/(2)` mole of `D_(2)O`. Mass of `(1)/(2)" mole of "H_(2)O=(1)/(2)xx18="9 g. Mass of "(1)/(2)" mole of "(1)/(2)" mole of "D_(2)O=(1)/(2)(2xx2+16)="10 g. Hecne, molar mass of the givne sample of water"=9+10="19 g mol"^(-1)`.