Question

What is observed when sulphur dioxide is passed through
(a) water (b) lime water
Also,write chemical equation for the reaction that take place

Answer 1

SOLUTION:

(i) When $\red{SO_{2}}$ is passed through water then Sulphurous acid is formed.

Now, the aqueous solution(aq) of $\red{SO_{2}}$ turn the blue litmus to red. (Showing acidic nature)

$\boxed{\blue{SO_{2}(g)+H_{2}O(l) \rightleftharpoons \blue{H_{2}SO_{3}(aq)}}}$

Here,

SO₂ = Sulfur Dioxide

H₂O = water    

H₂SO₃ = Sulphurous acid

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(ii) When $\red{SO_{2}}$ is passed through line water then Calcium Sulphite is formed which is white precipitate. It reacts with excess $\red{SO_{2}}$ to form Hydrogen Sulphite.

So, the chemical equation is

$\boxed{\pink{Ca(OH)_{2}+SO_{2} \longrightarrow CaSO_{3}+H_{2}O }}$

Here,

Ca(OH)₂ = lime water  

SO₂ = Sulfur dioxide

CaSO₃ = Calcium sulphite  

H₂O = Water

           

Also,

$\boxed{\purple{CaSO_{3}+H_{2}O+ SO_{2} (excess)\longrightarrow Ca(HSO_{3})_{2}}}$

Here,

CaSO₃ = Calcium sulphite

H₂O = water  

SO₂ = Sulphur dioxide

Ca(HSO₃)₂ = Calcium bisulphite

Answer 2

$\color{red} {} SOLUTION:-$

i) When SO² is passed through water, sulphurous acid is formed. The aqueous solution of SO ² turns blue litmus red.

$\color{orange} {}SO ²+H ²O⇌H ²O+SO ³$

(ii) But when SSO² is passed through lime water, calcium sulphite (white ppt.) is formed, which reacts with excess SO ² to form calcium hydrogen sulphite.

The chemical equation for the reactions are:

$\color{green} {}Ca(OH)²+SO²=CaSO ³+H ²0+CaSO ³+SO² +H²O=Ca(HSO )³$

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$\color{MAGENTA} {}CHEMICAL .EQUATION$⬆️

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