Calculate the mass of the precipitate that precipitated from the interaction of 980 g
Calculate the mass of the precipitate that precipitated from the interaction of 980 g of a 20% solution of copper sulfate (2) with potassium hydroxide.
Given:
m (CuSO4) = 980 g
w% (CuSO4) = 20%
To find:
m (draft) -?
Decision:
CuSO4 + 2KOH = K2SO4 + Cu (OH) 2, – we solve the problem, relying on the composed reaction equation:
1) Find the mass of copper sulfate in the reacted solution:
m (CuSO4) = 980 g * 0.2 = 196 g
2) Find the amount of copper sulfate:
n (CuSO4) = m: M = 196 g * 160 g / mol = 1.225 mol
3) We compose a logical expression:
If 1 mol of CuSO4 gives 1 mol of Cu (OH) 2,
then 1.225 mol of CuSO4 will give x mol of Cu (OH) 2,
then x = 1.225 mol.
4) Find the mass of copper hydroxide precipitated during the reaction:
m (Cu (OH) 2) = n * M = 1.225 mol * 98 g / mol = 120.05 g.
Answer: m (Cu (OH) 2) = 120.05 g.