Practical Chemistry Question 5
Question 5 - 2024 (30 Jan Shift 1)
Given below are two statements:
Statement-I: The gas liberated on warming a salt with dil $\mathrm{H}{2} \mathrm{SO}{4}$, turns a piece of paper dipped in lead acetate into black, it is a confirmatory test for sulphide ion.
Statement-II: In statement-I the colour of paper turns black because of formation of lead sulphite. In the light of the above statements, choose the most appropriate answer from the options given below:
(1) Both Statement-I and Statement-II are false
(2) Statement-I is false but Statement-II is true
(3) Statement-I is true but Statement-II is false
(4) Both Statement-I and Statement-II are true.
Show Answer
Answer (3)
Solution
$$ \begin{array}{r} \mathrm{Na}{2} \mathrm{~S}+\mathrm{H}{2} \mathrm{SO}{4} \rightarrow \mathrm{Na}{2} \mathrm{SO}{4}+\mathrm{H}{2} \mathrm{~S} \text { athon } \ \left(\mathrm{CH}{3} \mathrm{COO}\right){2} \mathrm{~Pb}+\mathrm{H}{2} \mathrm{~S} \rightarrow \mathrm{PbS}+2 \mathrm{CH}{3} \mathrm{COOH} \end{array} $$
Black lead sulphide
