Why is HF a good oxidizing agent, while HI a good reducing agent?

Answer 1

Hello there!

Looking on the periodic table, Fluorine is more electronegative than Iodine, meaning it wants to steal electrons more readily. Thus, it is better at stealing electrons. An oxidizing agent (HF) is one that causes other compounds to "lose electrons", hence that oxidizing agent would gain the electron. If HF is more electronegative than HI (meaning it hugs electrons), then it is better at stealing/oxidizing other compounds compared to HI.

Hope that helps!