Question

Assertion :On adding dilute hydrochloric acid to the reaction mixture, white precipitate disappears. Reason: $BaS{O}_3$ is a salt of a weak acid $\left(H_{2}S{O}_3\right)$, therefore dilute acid such as $HCl$ decomposes barium sulphite to produce sulphur dioxide gas which has the smell of burning sulphur.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

Dilute hydrochloric acid $\left(HCl\right)$ decomposes barium sulphite to form barium chloride ($BaC{l}_2$) , sulphur dioxide ($S{O}_2$) and water ($H_{2}O$). Since barium chloride is soluble in water, thus white precipitate disappears.

$BaS{O}_3+2HCl\to BaC{l}_2+S{O}_2+H_{2}O$