Question

How many grams of magnesium (Mg, 24.30 g/mol) are in 7.43x10^22 atoms of Mg?

Answer 1

Given the number of Mg atoms is $7.43 * 10^{22} atoms$

We know that 1 mol of any substance has Avogadro number $(6.022 * 10^{23})$ of formula units.

Converting number of atoms to mol:

$7.43 * 10^{22} atoms * \frac{1 mol}{6.022*10^{23} atoms} = 0.123 mol Mg$

Converting mol to mass of Mg:

$0.123 mol * \frac{24.30 g}{1 mol} = 2.99 g Mg$

Therefore mass of Mg is 2.99 g