Question

An atom of an element weighs 3.38× 10–23 g. What is the atomic mass of this element in atomic mass units?

Answer 1

Answer: The atomic mass of this element in atomic mass units is 20.3

Explanation:

According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number $6.023\times 10^{23}$ of particles.

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Let atomic mass of element is X amu

$6.023\times 10^{23}$ atoms weigh = X amu

1 atom weigh = $\frac{X}{6.023\times 10^{23}}\times 1=3.38\times 10^{-23}amu$

$X=20.3amu$

Atomic mass of this element in atomic mass units is 20.3