Mass precentage of deuterium in heavy water is

Options

A. same as that of protium in water
B. 11.1
C. 20
D. Cannot be predicated

Answer

C

Explanation

Formula of heavy water is `D_(2)O`, i.e. molecular mass = 20
`% "of deuterium"=(4 xx 100)/(20)`
`= 20%`