Mixed a solution weighing 10 g with a mass fraction of argentum nitrate 30% with a solution of potassium
Mixed a solution weighing 10 g with a mass fraction of argentum nitrate 30% with a solution of potassium chloride weighing 15.5 g and a mass fraction of KCL 3%. Calculate the mass of the sediment that has formed.
Given:
m solution (AgNO3) = 10 g
ω (AgNO3) = 30%
m solution (KCl) = 15.5 g
ω (KCl) = 3%
Find:
ω (sediment) -?
Solution:
1) AgNO3 + KCl => AgCl ↓ + KNO3;
2) m (AgNO3) = ω (AgNO3) * m solution (AgNO3) / 100% = 30% * 10/100% = 3 g;
3) n (AgNO3) = m (AgNO3) / M (AgNO3) = 3/170 = 0.02 mol;
4) m (KCl) = ω (KCl) * m solution (KCl) / 100% = 3% * 15.5 / 100% = 0.47 g;
5) n (KCl) = m (KCl) / M (KCl) = 0.47 / 74.5 = 0.01 mol;
6) n (AgCl) = n (KCl) = 0.01 mol;
7) m (AgCl) = n (AgCl) * M (AgCl) = 0.01 * 143.5 = 1.4 g.
Answer: The mass of AgCl is 1.4 g.
