Oridinary water contain one part of heavy water per 6000 parts of water by weight. The number of heavy water molecules present in a drop of water of volume 0.01 mL is (density of water 1 g/mL)

Options

A. `2.5xx10^(16)`
B. `5xx10^(17)`
C. `5xx10^(16)`
D. `7.5xx10^(16)`

Answer

C

Explanation

0.01 ml = 0.01 gm
`6000 gm H_(2)Orarr1 gm D_(2)O`
`0.01 gmH_(2)Orarr? =(0.01)/(6000)gmD_(2)O`
`(0.01)/(6000xx20)` moles
`=(0.01)/(6000xx20)xx6xx10^(23)` molecules `=5xx10^(16)`