How is sulphurdioxide gas prepared in laboratory? Write reactions to show SO 2 acts as both an oxidising as well as a reducing agent. [3+2]

Preparation of Sulphur Dioxide ( SO 2 ) in the Laboratory Sulphur dioxide ( SO 2 ) is commonly prepared in the laboratory by heating sodium sulphite ( Na 2SO 3 ) or sulphuric acid ( H 2SO 4 ) with copper ( Cu ) . The most common method involves the reaction of dilute sulphuric acid with sodium sulphite : Na 2SO 3 + H 2SO 4 Na 2SO 4 + SO 2 + H 2O Procedure: 1. A small amount of sodium sulphite ( Na 2SO 3 ) is taken in a test tube. 2. Dilute sulphuric acid ( H 2SO 4 ) is carefully added to the test tube. 3. The mixture is gently heated, producing colourless SO 2 gas, which can be identified by its pungent smell and ability to turn acidified potassium dichromate ( K 2Cr 2O 7 ) green. SO 2 as an Oxidising and Reducing Agent 1. SO 2 as a Reducing Agent SO 2 acts as a reducing agent by getting oxidised to SO 3 or SO 4^2 . For example: Reaction with bromine water : SO 2 + Br 2 + 2H 2O H 2SO 4 + 2HBr Here, SO 2 is oxidised to H 2SO 4 (sulphur’s oxidation state increases from +4 to +6 ), while bromine ( Br 2 ) is reduced to HBr . 2. SO 2 as an Oxidising Agent SO 2 acts as an oxidising agent by getting reduced to sulphur ( S ) . For example: Reaction with hydrogen sulphide ( H 2S ) : SO 2 + 2H 2S 3S + 2H 2O Here, SO 2 is reduced to sulphur (sulphur’s oxidation state decreases from +4 to 0 ), while H 2S is oxidised to sulphur.

How is sulphurdioxide gas prepared in laboratory? Write reactions to show SO 2 acts as… – Chemistry NEB 2076 (old course) Solution

Preparation of Sulphur Dioxide ( $SO X_{2}$ ) in the Laboratory

Sulphur dioxide ( $SO X_{2}$ ) is commonly prepared in the laboratory by heating sodium sulphite ( $Na X_{2} SO X_{3}$ ) or sulphuric acid ( $H X_{2} SO X_{4}$ ) with copper ( $Cu$ ). The most common method involves the reaction of dilute sulphuric acid with sodium sulphite:

Na₂SO₃+H₂SO₄HeatSO₂+Na₂SO₄+2H₂O

Preparation of SO₂ by heating sodium sulphite with dilute sulphuric acid

$Na X_{2} SO X_{3} + H X_{2} SO X_{4} Na X_{2} SO X_{4} + SO X_{2} + H X_{2} O$

Procedure:

A small amount of sodium sulphite ( $Na X_{2} SO X_{3}$ ) is taken in a test tube.
Dilute sulphuric acid ( $H X_{2} SO X_{4}$ ) is carefully added to the test tube.
The mixture is gently heated, producing colourless $SO X_{2}$ gas, which can be identified by its pungent smell and ability to turn acidified potassium dichromate ( $K X_{2} Cr X_{2} O X_{7}$ ) green.

$SO X_{2}$ as an Oxidising and Reducing Agent

SO₂+2H₂SRoom temperature3S+2H₂O

SO₂ as oxidising agent (reduction to S)

SO₂+Cl₂Dark, dry conditionsSO₂Cl₂

SO₂ as reducing agent (oxidation to SO₂Cl₂)

1. $SO X_{2}$ as a Reducing Agent

$SO X_{2}$ acts as a reducing agent by getting oxidised to $SO X_{3}$ or $SO X_{4} X^{2 -}$ . For example:

Reaction with bromine water: $SO X_{2} + Br X_{2} + 2 H X_{2} O H X_{2} SO X_{4} + 2 HBr$ Here, $SO X_{2}$ is oxidised to $H X_{2} SO X_{4}$ (sulphur’s oxidation state increases from +4 to +6), while bromine ( $Br X_{2}$ ) is reduced to $HBr$ .

2. $SO X_{2}$ as an Oxidising Agent

$SO X_{2}$ acts as an oxidising agent by getting reduced to sulphur ( $S$ ). For example:

Reaction with hydrogen sulphide ( $H X_{2} S$ ): $SO X_{2} + 2 H X_{2} S 3 S + 2 H X_{2} O$ Here, $SO X_{2}$ is reduced to sulphur (sulphur’s oxidation state decreases from +4 to 0), while $H X_{2} S$ is oxidised to sulphur.

SO₂+2H₂SRoom temperature3S+2H₂O

SO₂ oxidises H₂S to sulphur (oxidation state of S in SO₂: +4 → 0 in S)

How is sulphurdioxide gas prepared in laboratory? Write reactions to show SO 2 acts as both an oxidising as well as a reducing agent. [3+2]

Preparation of Sulphur Dioxide ( $SO X_{2}$ ) in the Laboratory

$SO X_{2}$ as an Oxidising and Reducing Agent

1. $SO X_{2}$ as a Reducing Agent

2. $SO X_{2}$ as an Oxidising Agent

Discussion

More Chemistry questions

How is sulphurdioxide gas prepared in laboratory? Write reactions to show SO 2 acts as both an oxidising as well as a reducing agent. [3+2]

Preparation of Sulphur Dioxide (SOX2​) in the Laboratory

SOX2​ as an Oxidising and Reducing Agent

1. SOX2​ as a Reducing Agent

2. SOX2​ as an Oxidising Agent

Discussion

More Chemistry questions

Preparation of Sulphur Dioxide ( $SO X_{2}$ ) in the Laboratory

$SO X_{2}$ as an Oxidising and Reducing Agent

1. $SO X_{2}$ as a Reducing Agent

2. $SO X_{2}$ as an Oxidising Agent