Question

Among the following halogens \(F_2, \, Cl_2, \, Br_2, \, \text{and} \, I_2\)
Which can undergo disproportionation reaction?

• A. Only \(I_2\)
• B. \(Cl_2, \, Br_2, \, \text{and} \, I_2\)
• C. \(F_2, \, Cl_2, \, \text{and} \, Br_2\)
• D. \(F_2 \, \text{and} \, Cl_2\)

Answer 1

The Correct Option is B

This inquiry concerns which of the halogens \( F_2, \, Cl_2, \, Br_2, \) and \( I_2 \) are capable of undergoing disproportionation. The definition of a disproportionation reaction is provided, followed by an examination of each halogen to ascertain its capacity for this reaction type.

Disproportionation Defined: A disproportionation reaction is a redox process where an element is simultaneously oxidized and reduced, yielding two distinct products with different oxidation states.

The following analysis determines which halogens can undergo disproportionation:

1. \(F_2\): Fluorine, being the most electronegative element, does not disproportionate. It exists in its highest oxidation state as fluoride, \(F^-\), and cannot be further oxidized.
2. \(Cl_2\): Chlorine can disproportionate. It can be oxidized to hypochlorite (\(ClO^-\)) and reduced to chloride (\(Cl^-\)). An illustrative reaction is: \(2Cl_2 + 2OH^- \rightarrow ClO^- + Cl^- + H_2O\).
3. \(Br_2\): Bromine undergoes disproportionation in alkaline conditions to form bromate (\(BrO_3^-\)) and bromide (\(Br^-\)).
4. \(I_2\): Iodine disproportionates into iodate (\(IO_3^-\)) and iodide (\(I^-\)).

Based on this analysis, the halogens that can undergo disproportionation reactions are:

• \(Cl_2\)
• \(Br_2\)
• \(I_2\)

Fluorine (\(F_2\)) does not exhibit this behavior. Consequently, the halogens capable of disproportionation are \(Cl_2, \, Br_2, \, \text{and} \, I_2\).