Question

The number of electrons in oxygen atom in 0.3 g molecule of Mohr's salt $FeS{O}_4(N{H}_4{)}_{2}S{O}_4.6H_{2}O$ is:

• A. $0.5N_A$
• B. $4.5N_A$
• C. $6.5N_A$
• D. $33.6N_A$

Answer 1

The correct option is D $33.6N_A$

Mohr salt = 0.3 g molecule

1 g molecule = $6.022\times {10}^{23}$

So, in 0.3 g molecule = $0.3\times 6.022\times {10}^{23}$

The total oxygen atom in Mohr salt is 14.

Total molecule $=14\times 0.3\times 6.022\times {10}^{23}$
= $4.2\times 6.022\times {10}^{23}$
As we know that one atom of oxygen contains eight electrons.
Total electrons $=4.2\times 8\times 6.022\times {10}^{23}$
$=33.6\times 6.022\times {10}^{23}$
Avogadro number is also represented by $N_A$.