Question

Calculate the total number of electrons present in 1.4 g of dinitrogen gas.

Answer 1

Molar mass of dinitrogen $\left(N_2\right)=28gmo{l}^{-1}$
Thus, $1.4gof{N}_2=\frac{1.4}{28}=0.05mol$
$=0.05\times 6.02\times {10}^{23}$ number of molecules
$=3.01\times {10}^{23}$ number of molecules
Now, 1 molecule of $N_2$ contains 14 electrons
Therefore, $3.01\times {10}^{23}$ molecules of $N_2$ contains $=14\times 3.01\times {10}^{23}$
$=4.214\times {10}^{23}$ electrons