Question

$4.6\times {{10}^{22}}$ atoms of an element weigh 13.8 g. The atomic weight of that element is

• A. 290
• B. 180
• C. 34.4
• D. 10.4

Answer 1

Answer: (B)

$4.6\times {{10}^{22}}$ atoms weight $=13.8\,g$ Hence, $6.02\times {{10}^{13}}$ atoms will weight $=\frac{13.8\times 6.02\times {{10}^{23}}}{4.6\times {{10}^{22}}}=180.6g$ (molar mass)