Which of the following statements about elements in Group VII is correct?

Step 1: Analyze the question We are asked about the oxidizing power of the Group VII elements (halogens). A halogen acts as an oxidizing agent by gaining electrons, so it is itself reduced.

Step 2: The concept Oxidizing power decreases down the group:

F₂ > Cl₂ > Br₂ > I₂

This is because the atoms get larger going down the group, so the nucleus attracts an incoming electron less strongly. A more reactive halogen (higher up) can displace a less reactive halogen (lower down) from its salt solution, by oxidizing the halide ion.

Step 3: Check each option

• A. Br₂ will oxidize Cl⁻ is false. Br₂ is a weaker oxidizing agent than Cl₂, so it cannot take electrons from Cl⁻. No reaction occurs.
• B. F₂ has the least tendency to be reduced is false. F₂ has the greatest tendency to be reduced, since it is the strongest oxidizing agent.
• C. Cl₂ will oxidize I⁻ is true. Cl₂ is stronger than I₂, so it displaces iodine: Cl₂ + 2I⁻ → 2Cl⁻ + I₂ The solution turns brown as iodine is liberated.
• D. I₂ is a stronger oxidizing agent than F₂ is false. It is the other way round: F₂ is the strongest and I₂ the weakest.

Step 4: Answer The correct option is C.

Exam tip: Remember that "a halogen higher in the group displaces the ones below it". So Cl₂ can displace Br⁻ and I⁻, Br₂ can displace only I⁻, and I₂ displaces none of them. F₂ is the strongest oxidizer, so it is the most easily reduced.