Question

Determine the total number of atoms present in $7N{H}_3$.

• A. 10
• B. 4
• C. 11
• D. 28

Answer 1

The correct option is D

28

In $7N{H}_3$, there are 7 molecules of ammonia. To know the total number of atoms, we need to know the individual number of atoms present and then multiply by 7. So,

Number of N atoms in $7N{H}_3$ = 7 $\times$ 1 = 7

Number of H atom in $7N{H}_3$ = 3 $\times$ 7 = 21

Total number of atoms = Number of N atoms + Number of H atoms = 7 + 21 = 28

The total number of atoms present in $7N{H}_3$ is 28.