Question

Which equations represent precipitation reactions? More than one can be chosen.

A. Na2S + FeBr2 → 2NaBr + FeS
B. MgSO4 + CaCl2 → MgCl2 + CaSO4
C. LiOH + NH4I → LiI + NH4OH
D. 2NaCl + K2S → Na2S + 2KCl
E. AgNO3 + NaCl → AgCl + NaNO3

Answer 1

A. Na₂S + FeBr₂ → 2NaBr + FeS.

B. MgSO₄ + CaCl₂ → MgCl₂ + CaSO₄.

E. AgNO₃ + NaCl → AgCl + NaNO₃.

Answer 2

Answer is:

A. Na₂S + FeBr₂ → 2NaBr + FeS.

B. MgSO₄ + CaCl₂ → MgCl₂ + CaSO₄.

E. AgNO₃ + NaCl → AgCl + NaNO₃.

Iron sulfide (FeS) has low solubility in water.

Calcium sulfate (CaSO₄) has low solubility in water and it will form white precipitate.

Silver chloride (AgCl) has low solubility in water and it will form white precipitate.