Question

4.6×1022 atoms of an element weighs 13.8 g. The atomic mass of the element is

• A. 180
• B. 20
• C. 1
• D. 30

Answer 1

The correct option is A 180

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

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

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