Question

Which equations represent precipitation reactions?

Na2S + FeBr2 → 2NaBr + FeS
MgSO4 + CaCl2 → MgCl2 + CaSO4
LiOH + NH4I → LiI + NH4OH
2NaCl + K2S → Na2S + 2KCl
AgNO3 + NaCl → AgCl + NaNO3


Multiple answers

Answer 1

HEY I GOT YO ANSWER

THE ANSWERS ARE A B AND DA LAST ONE

Answer 2

Na₂S + FeBr₂ → 2NaBr + FeS(s)

MgSO₄ + CaCl₂ → MgCl₂ + CaSO₄(s)

AgNO₃ + NaCl → AgCl(s) + NaNO₃

Step-by-step explanation:

You must recall the pertinent solubility rules:

1. Salts of Group 1 elements (Li⁺, Na⁺, K⁺) and of NH₄⁺ are soluble
2. Salts containing nitrate ion (NO₃⁻) are soluble.
3. Salts containing Cl⁻, Br⁻, and I⁻ are generally soluble. An important exception is Ag⁺. Thus, AgCl is insoluble.
4. Most sulfate (SO₄²⁻) salts are soluble. An important exception is CaSO₄, which is insoluble.
5. Most sulfide (S²⁻) salts of transition metals are insoluble.

Na₂S + FeBr₂ → 2NaBr + FeS(s)

NaBr is soluble (Rule 1). FeS is insoluble (Rule 5), so a precipitate forms.

MgSO₄ + CaCl₂ → MgCl₂ + CaSO₄(s)

MgSO₄ is soluble (Rule 3). CaSO₄ is insoluble (Rule 4), so a precipitate forms.

AgNO₃ + NaCl → AgCl(s) + NaNO₃

NaNO₃ is soluble (Rule 1). AgCl is insoluble (Rule 3) so a precipitate forms.

LiOH + NH₄I → LiI + NH₄OH and 2NaCl + K₂S → Na₂S + 2KCl

All products are soluble (Rule 1), so these are not precipitation reactions.