Answer:
36.23 %
Explanation:
Let's assume we have 1 mol of FeCl₂ · 4H₂O. In that case we would have:
- 1 mol of FeCl₂, weighing 126.75 g (that's the molar mass of FeCl₂), and
- 4 moles of H₂O, weighing (4 * 18 g/mol) 72 g.
Now we can calculate the percent by mass of water:
- % mass = mass of water / total mass * 100%
- % mass = [tex]\frac{72}{72+126.75}[/tex] * 100% = 36.23 %
