Question

When barium chloride and sodium sulphate react together in aqueous solution, an insoluble substance is formed with sodium chloride in the aqueous solution. This reaction is an example of:

• A. Combination reaction
• B. Decomposition reaction
• C. Displacement reaction
• D. Double displacement reaction

Hint:

In a double displacement reaction, parts of two compounds exchange to form two new compounds — often forming a precipitate, gas, or water.

Answer 1

The Correct Option is D

When BaCl$_2$ (barium chloride) and Na$_2$SO$_4$ (sodium sulphate) are mixed in aqueous solution, a white precipitate of barium sulphate (BaSO$_4$) forms, and sodium chloride (NaCl) remains in solution. \[ \text{BaCl}_2 + \text{Na}_2\text{SO}_4 \rightarrow \text{BaSO}_4 \downarrow + 2\text{NaCl} \] This is a classic double displacement reaction, where ions are exchanged between two compounds and one of the products is insoluble (precipitate).