Answer:
6.696 g of water (H₂O)
Step-by-step explanation:
First we calculate the number of moles of barium hydroxide:
number of moles = mass / molecular weight
number of moles = 31.8 / 171.3 = 0.186 moles of barium hydroxide
Form the chemical reaction we may devise the following reasoning:
if 1 mole of barium hydroxide produces 2 moles of water
then 0.186 moles of barium hydroxide produces X moles of water
X = (0.186 × 2) / 1 = 0.372 moles of water
mass = number of moles × molecular weight
mass of water = 0.372 × 18 = 6.696 g