A spoon of table salt (NaCl) contains 12.5 grams. Calculate the number of moles it contains.
Difficulty: Easy
Mass of sodium chloride (NaCl) = 12.5 g
Molar mass of sodium chloride (NaCl) = 23 + 35.5 = 58.5 g
$\text{Number of moles} = \frac{\text{Mass in grams}}{\text{Molar mass}}$
$\text{Number of moles} = \frac{12.5}{58.5}$
$\text{Number of moles} = 0.21 \text{ moles}$