Question

$4.6\times {10}^{22}$ atoms of an element weighs $13.8g$. The atomic mass of the element is:

• A. 290
• B. 180
• C. 34.4
• D. 104

Answer 1

The correct option is B

180

$4.6\times {10}^{22}atoms\to 13.8g$

$6.023\times {10}^{23}\to xg$

$x=\frac{13.8\times 6.023\times {10}^{23}}{4.6\times {10}^{22}}=180$