Question

Number of molecules in 14g of carbon monoxide is

• A. $12.044\times {10}^{23}$
• B. $6.022\times {10}^{23}$
• C. $3.011\times {10}^{23}$
• D. $1.5050\times {10}^{23}$

Answer 1

The correct option is C

$3.011\times {10}^{23}$

1. Atomic mass of carbon ($\mathrm{C}$) = 12g
2. Atomic mass of oxygen ($\mathrm{O}$) = 16g
3. Therefore, molecular mass of carbon monoxide ($\mathrm{CO}$) = 12+16 =$28g$
4. 28g of $\mathrm{CO}$ has molecules = $6.022\times {10}^{23}$
5. Thus, 14g of $\mathrm{CO}$ has half the molecule as that of 28g of $\mathrm{CO}$ = $\frac{6.022\times {10}^{23}}{2}=\mathit{}\mathit{3}\mathit{.}\mathit{011}\mathit{\times }{\mathit{10}}^{\mathit{23}}$