Question

Which type of reaction produces precipitates which are ionic compounds?

• A. Decomposition
• B. Double Replacement
• C. Synthesis
• D. Single Replacement

Answer 1

Answer: (B)

Double Replacement

Double replacement reactions, also called as double displacement, exchange or metathesis reactions occur when parts of ionic compounds are exchanged, making two new compounds.

However, if during this reaction, a product is formed such that it is insoluble in water then it leads to precipitation of the product. There is a formation of an insoluble mass at the bottom of the test tube which is known as the precipitate.

An example of the double replacement reaction where an ionic compound is precipitated is:-

$BaC{l}_2+N{a}_{2}S{O}_4\to BaS{O}_4+2NaCl$

Here, $BaS{O}_4$ is an ionic product that forms an insoluble white mass as it is insoluble in water.

Hence, the correct answer is the option (B).