# You have 40g of MgCl2. How many atoms of Cl are in the sample?

Mar 4, 2018

5.07 × 10^23

#### Explanation:

Molar mass of $\text{MgCl"_2 = "95 g/mol}$

Moles of ${\text{MgCl}}_{2}$ in given sample $= \text{40 g"/"95 g/mol" = "0.421 mol}$

Moles of $\text{Cl}$ atoms in given sample = 2 × "0.421 mol" = "0.842 mol"

Number of $\text{Cl}$ atoms = 0.842 cancel"mol" × (6.022 × 10^23)/cancel"mol" = 5.07 × 10^23