Question

In a closed container there is a mixture of SO₂, CO₂ and O₂ gas. which sequence of reagent can be helpful to separate them.

(i) lime water
(ii) acidified potassium dichromate
(iii) alkaline pyragallol.

(a) (i), (ii), (iii)
(b) (ii), (i), (iii)
(c) (iii), (ii), (i)
(d) (iii), (i). (ii)

Answer 1

The sequence of reagents to separate the gases is (c) (iii), (ii), (i).

Step-by-step explanation:

To separate a mixture of SO2, CO2, and O2 gas in a closed container, you would use a sequence of reagents that react selectively with each individual gas. The appropriate sequence for the separation would be (a): lime water, acidified potassium dichromate, and alkaline pyrogallol.

1. Lime water (calcium hydroxide solution), which reacts with CO2 to form calcium carbonate (CaCO3), a precipitate which can be filtered out.
2. Acidified potassium dichromate, which can oxidize SO2 into sulfuric acid (H2SO4), removing SO2 from the mixture as it gets dissolved in the acidified solution.
3. Alkaline pyrogallol which effectively absorbs O2 gas due to its property of being a reducing agent in alkaline solution.

By employing this sequence, each of the gases reacts in turn with a specific reagent to either precipitate out or become absorbed, thus allowing for the separate collection of each gas.