As a result of a chemical reaction between magnesium hydroxide and nitrous acid

As a result of a chemical reaction between magnesium hydroxide and nitrous acid, 8 liters of water were released. How many grams of magnesium hydroxide did this reaction take?

Given:
V (H2O) = 8 l
To find:
m (Mg (OH) 2)
Decision:
Mg (OH) 2 + 2HNO2 = Mg (NO2) 2 + 2H2O
n (H2O) = V / Vm = 8 L / 22.4 L / mol = 0.357 mol
n (H2O): n (Mg (OH) 2) = 2: 1
n (Mg (OH) 2) = 0.357 mol / 2 = 0.18 mol
m (Mg (OH) 2) = n * M = 0.18 mol * 58 g / mol = 10.44 g
Answer: 10.44 g