Question

Which of these has the maximum number of molecules?

• A. $7$ g $N_2$
• B. $2$ g $H_2$
• C. $16$ g $N{O}_2$
• D. $16$ g $O_2$

Answer 1

The correct option is B $2$ g $H_2$

The expression for the number of molecules is given as:

$Numberofmolecules=\frac{Mass}{Molecularmass}\times N_A$,

where, $N_A$ is the Avogadro number.

$N_{2}contains\frac{7\times N_A}{28}=0.25\times N_{A}molecules$

$H_{2}contains\frac{2\times N_A}{2}=1\times N_{A}molecules$

$N{O}_{2}contains\frac{16\times N_A}{46}=0.35\times N_{A}molecules$

$O_{2}contains\frac{16\times N_A}{32}=0.5\times N_{A}molecules$