Which of the following statement is incorrect ?

Options

A. `NO` is heavier than `O_2`
B. The formula of heavy water in `D_2 O`.
C. Nitrogen diffuses faster than oxygen through an orifice.
D. `NH_3` can be used as a refrigerant.

Answer

A

Explanation

Molecular weight `(Mw) NO = 14 + 16 = 30`
Vapour density `= (Mw)/(2) = (30)/(2) = 15`
Molecular weight `(Mw) of O_2 = 16 + 16 = 32`
Vapour density `= (Mw)/(2) = (32)/(2) = 16`
Therefore, `NO` is lighter than `O_2`.
Hence statement (a) is incorrect.
( c) `Mw of N_2 = 28, Mw of O_2 = 32`,
Rate of diffusion or effusion in inversely proportional to the square root of their molecular weight or vapour densities.
Since the `Mw` of `N_2` is less than `Mw` of `O_2`, so `N_2` diffuses faster than `O_2`.