A copper sulfate solution was added to 200 g of a 30% sodium hydroxide solution. Find the mass of the sediment.

1. We draw up a chemical equation, not forgetting to put down the coefficients:

СuSO4 + 2NaOH = Cu (OH) 2 + Na2SO4.

2. Find the mass of NaOH:

m (NaOH) = m (solution) * ω = 200 * 0.3 = 60g.

3. Find the amount of NaOH substance:

n (NaOH) = m / M = 60/40 = 1.5 mol.

4. Find the amount of substance Cu (OH) 2 (based on the coefficients in the equation):

n (Cu (OH) 2) = n (NaOH) / 2 = 1.5 / 2 = 0.75 mol.

5. Find the mass of Cu (OH) 2:

m (Cu (OH) 2) = M * n = 98 * 0.75 = 73.5g.

Answer: m (Cu (OH) 2) = 73.5g.