Question

which of the following is a precipitation reaction?
2 lioh(aq) + h₂so₄(aq) → li₂so₄(aq) + 2 h₂o(l)
2 hcl(aq) + ca(oh)₂(aq) → 2 h₂o(l) + cacl₂(aq)
2 k(s) + 2 h₂o(l) → 2 koh(aq) + h₂(g)
nacl(aq) + agno₃(aq) → agcl(s) + nano₃(aq)
cuso₄(aq) + zn(s) → znso₄(aq) + cu(s)

Explanation:

A precipitation reaction is a type of chemical reaction in which two aqueous solutions react to form an insoluble solid (precipitate). In the reaction \(NaCl(aq)+AgNO_{3}(aq)\to AgCl(s)+NaNO_{3}(aq)\), \(AgCl\) is the insoluble precipitate formed. The other reactions:

• \(2LiOH(aq)+H_{2}SO_{4}(aq)\to Li_{2}SO_{4}(aq)+2H_{2}O(l)\) is an acid - base neutralization reaction (formation of water).
• \(2HCl(aq)+Ca(OH)_{2}(aq)\to 2H_{2}O(l)+CaCl_{2}(aq)\) is also an acid - base neutralization reaction.
• \(2K(s)+2H_{2}O(l)\to 2KOH(aq)+H_{2}(g)\) is a single - displacement reaction (metal reacting with water to form a base and hydrogen gas).
• \(CuSO_{4}(aq)+Zn(s)\to ZnSO_{4}(aq)+Cu(s)\) is a single - displacement reaction (metal displacement).

Answer:

\(NaCl(aq)+AgNO_{3}(aq)\to AgCl(s)+NaNO_{3}(aq)\)