Practicing Success

Target Exam

CUET

Subject

Chemistry

Chapter

Organic: Polymers

Question:

Identify \('X'\) along with oxidation state of halogen in the given reaction:

\(3Cl_2 + 6NaOH \longrightarrow 5NaCl + X + 3H_2O\) (hot and conc.)

Options:

\(NaClO_2\), +3

\(NaClO_3\), +5

\(NaClO_2\), +7

\(NaClO_3\), +1

Correct Answer:

\(NaClO_3\), +5

Explanation:

The correct answer is option 2. \(NaClO_3\), +5.

Let us break down the explanation step by step:

1. Understanding the Reaction:

The given reaction is a disproportionation reaction of chlorine (\(Cl_2\)) in the presence of hot and concentrated sodium hydroxide (\(NaOH\)):

\[ 3Cl_2 + 6NaOH \longrightarrow 5NaCl + X + 3H_2O \]

2. Identification of \(X\):

In the reaction, chlorine (\(Cl_2\)) is both oxidized and reduced simultaneously. It is oxidized to form a compound represented by \(X\) and reduced to form sodium chloride (\(NaCl\)). We need to identify \(X\) and determine its composition.

3. Possible Chlorine Compounds:

Chlorine can exhibit various oxidation states, including -1, +1, +3, +5, and +7. To find \(X\), we need to consider compounds where chlorine has a positive oxidation state.

4. Oxidation States of Chlorine:

\(NaClO_2\): In this compound, chlorine has an oxidation state of +3.

\(NaClO_3\): In this compound, chlorine has an oxidation state of +5.

\(NaClO_2\): In this compound, chlorine has an oxidation state of +7.

\(NaClO_3\): In this compound, chlorine has an oxidation state of +1.

5. Selection of Correct Option:

Since the given reaction involves the formation of a compound (\(X\)) where chlorine is oxidized, and the options provide compounds with different oxidation states of chlorine, we need to choose the compound where chlorine has an oxidation state of +5. This corresponds to option (2) \(NaClO_3\).

Therefore, \(X\) in the reaction is \(NaClO_3\), and the oxidation state of chlorine in \(NaClO_3\) is +5. This compound is formed during the disproportionation of chlorine in hot and concentrated sodium hydroxide solution.