Halogen reactivity and displacement

Steps:

• Recall halogen reactivity decreases down group 7: F > Cl > Br > I, so oxidizing strength follows this order.
• A stronger halogen displaces a weaker one from its halide ion, e.g., Cl2 + 2Br- → 2Cl- + Br2.
• Evaluate B: Br2 cannot oxidize Cl- to Cl2 since Br is weaker oxidant than Cl.
• Test other options against reactivity and properties to identify errors.

Why B is correct:

• Bromine, being below chlorine in group 7, has lower oxidizing power and cannot displace Cl2 from NaCl solution per the displacement reaction rule.

Why the others are wrong:

• A: Bromine (Br2) added to AgNO3 forms no precipitate; AgBr (pale yellow) requires Br- ions, not free Br2.
• C: Fluorine forms anions (F-) by gaining electrons, not cations; statement is chemically impossible.
• D: Iodide ions (I-) are stronger reducing agents than chloride (Cl-) as I- oxidizes more easily to I2.

Final answer: B