Question

Calculate the mass of the following:

$0.2\mathrm{mol}$ atom of oxygen

Answer 1

• The mole formula is-
• $\mathrm{Mole}\left(\mathrm{mol}\right)=\frac{\mathrm{Mass}\left(\mathrm{g}\right)}{\mathrm{Molar}\mathrm{mass}(\mathrm{g}/\mathrm{mol})}$
• We can rearrange the formula to get the mass formula-
• $\mathrm{Mass}\left(\mathrm{g}\right)=\mathrm{Mole}\left(\mathrm{Mol}\right)\times \mathrm{Molar}\mathrm{mass}(\mathrm{g}/\mathrm{mol})$
• Molar mass of $\mathrm{O}$- $16\mathrm{g}/\mathrm{mol}$
• Mole of $\mathrm{O}$- $0.2\mathrm{mol}$
• We substitute these values in the mass formula.
• $\mathrm{Mass}=0.2\times 16$
• $\mathrm{Mass}=3.2\mathrm{g}$
• Hence, the mass of $0.2\mathrm{mol}$ of oxygen atoms is $3.2\mathrm{g}$.