Question

What is the mass of $3.01\times {10}^{22}$ molecules of $N{H}_3$?

• A. $6\text{g}$
• B. $2\text{g}$
• C. $0.85\text{g}$
• D. $10\text{g}$

Answer 1

The correct option is C $0.85\text{g}$

Mass of $6.023\times {10}^{23}$ molecules of $N{H}_3=17\text{g}$
Mass of $3.01\times {10}^{22}$ molecules of $N{H}_3=\frac{17\times 3.01\times {10}^{22}}{6.023\times {10}^{23}}=0.85\text{g}$