Question

The number of molecules in $109.5$ gm of $HCl$ $[H=1,Cl=35.5]$ is :

• A. $36.5\times 6.023\times {10}^{23}$
• B. $2\times 6.023\times {10}^{23}$
• C. $3.011\times {10}^{23}$
• D. $3\times 6.023\times {10}^{23}$

Answer 1

The correct option is D $3\times 6.023\times {10}^{23}$

As we know, one mole of each substance contains $N_A$ molecules so $109.5g$ of $HCl$ contains, $109.5\times \frac{N_A}{36.5}=3N_A=3\times 6.023\times {10}^{23}$.