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chem aqa alevel halogens question

how is I- (iodide ion) a better reducing agent than I2? and how's Cl2 a better oxidising agent than Cl-?
better reducing agent because the extra electron making it an iodide ion is much further away (larger atomic radius), so the attraction between it and the positive nucleus is weaker making it is easier to lose and reduce another species.

Cl2 is a better oxidising agent because the valence/outer shell is closer to the nucleus (smaller atomic radius) so it is easier to gain an electron due to stronger attraction.
Reply 2
Original post by george flowberry
better reducing agent because the extra electron making it an iodide ion is much further away (larger atomic radius), so the attraction between it and the positive nucleus is weaker making it is easier to lose and reduce another species.
Cl2 is a better oxidising agent because the valence/outer shell is closer to the nucleus (smaller atomic radius) so it is easier to gain an electron due to stronger attraction.

thank you!

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