Analytical Chemistry Question 155
Question: Sodium sulphite on heating with dilute $ HCl $ liberates a gas which
[NCERT 1972]
Options:
A) Turns lead acetate paper black
B) Turns acidified potassium dichromate paper green
C) Burns with a blue flame
D) Smells like vinegar
Show Answer
Answer:
Correct Answer: B
Solution:
$ Na_2S+dil\text{.2}HCl\to 2NaCl+H_2S $
$ H_2S\ +\ H_2SO_4\ +\ K_2Cr_2O_7\ \xrightarrow{acidic}\ K_2SO_4 $
$ +\ \underset{\text{(green)}}{\mathop{Cr_2{{(SO_4)}_3}}}\ +\ S $
BETA
