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 $H _2 SO _4$, 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

$$ \begin{array}{r} Na _2 S+H _2 SO _4 \rightarrow Na _2 SO _4+H _2 S \text { athon } \\ \left(CH _3 COO\right) _2 Pb+H _2 S \rightarrow PbS+2 CH _3 COOH \end{array} $$

Black lead sulphide