Question

Which represents a double replacement reaction and would occur?
A) NH4NO3(aq) + AgCIO3(aq) mc011-1.jpg AgNO3(aq) + NH4CIO3(aq)
B) Na2CO3(aq) + CaCl2(aq) mc011-2.jpg 2NaCl(aq) + CaCO3(s)
C) NaF(aq) + KCl(aq) mc011-3.jpg NaCl(aq) + KCl(aq)
D) NaCl(aq) mc011-4.jpg Na+(aq) + Cl-(aq)

Answer 1

The answer that your looking for is b

Answer 2

Answer: B) $Na_2CO_3(aq)+CaCl_2(aq)\rightarrow 2NaCl(aq)+CaCO_3(s)$

Explanation: A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.

Double replacement reactions are of two types: Precipitation reactions and neutralization reactions. In Precipitation reactions, an insoluble product is formed and in neutralization reactions , acid and base reacts to give slat and water.

$Na_2CO_3(aq)+CaCl_2(aq)\rightarrow 2NaCl(aq)+CaCO_3(s)$ is a precipitation reaction as calcium carbonate is formed as a precipitate.