Question

$3.011\times 10^{22}$ atoms of an element weighs $1.15g$ . The atomic mass of the element is

• A. 23
• B. 10
• C. 16
• D. 35.5

Answer 1

Answer: (A)

From Avogadro's law,

Avogadro's number = Atomic mass of the element

$\because 3.011\times 10^{22}$ atoms contain an element weigh $1.15g$

$\therefore 6.023\times 10^{23}$ atoms contain an element weigh

$=\frac{1.15\times 6.023\times 10^{23}}{3.011\times 10^{22}}=23$

Hence, atomic mass of the element is $23.$