Determine the mass of the precipitate obtained by merging solutions containing 56 g of 10%

Determine the mass of the precipitate obtained by merging solutions containing 56 g of 10% potassium hydroxide solution with an excess of iron (III) nitrate solution.

Given:
m solution (KOH) = 56 g
w (KOH) = 10% = 0.1
To find:
m (Fe (OH) 3)
Decision:
3KOH + Fe (NO3) 3 = Fe (OH) 3 + 3KNO3
m in-va (KOH) = w * m solution = 0.1 * 56 g = 5.6 g
n (KOH) = m / M = 5.6 g / 56 g / mol = 0.1 mol
n (KOH): n (Fe (OH) 3) = 3: 1
n (Fe (OH) 3) = 0.1 mol / 3 = 0.03 mol
m (Fe (OH) 3) = n * M = 0.03 mol * 107 g / mol = 3.21 g
Answer: 3.21 g