Question

$6.022\times {10}^{20}$ atoms of silver (at. mass 108 u) weigh

• A. $108\times {10}^3\mathrm{g}$
• B. $108\mathrm{g}$
• C. $0.108\mathrm{g}$
• D. $10.8\mathrm{g}$

Answer 1

The correct option is C

$0.108\mathrm{g}$

Explanation of the correct option:

The correct option is C:

From the given,

$$\begin{gathered} \mathrm{Atomic}\mathrm{mass}\mathrm{of}\mathrm{Silver}\left(\mathrm{Ag}\right)=108\mathrm{g} \\ 6.023\times {10}^{23}\mathrm{atoms}\mathrm{of}\mathrm{Ag}\mathrm{weigh}108\mathrm{g}. \\ 6.023\times {10}^{20}\mathrm{atoms}\mathrm{of}\mathrm{Ag}\mathrm{weigh}=\frac{108}{6.023\times {10}^{23}}\times 6.023\times {10}^{20} \\ =108\times {10}^{-3} \\ =0.108\mathrm{g} \end{gathered}$$

Hence, option (C) is correct.
$6.022\times {10}^{20}$ atoms of silver (at. mass 108 u) weigh $0.108\mathrm{g}$.