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gcse MCQ Chemistry question

Chlorine displaces iodide ions from potassium iodide. What is the oxidizing agent?
A)Chloride ions
B)Chlorine
C)Iodide ions
D)Iodine
The answer is B .When I came to answer, I knew it was gonna be A or B but how do you choose between both? Also, since the answer is B does that mean ions cannot be oxidizing agents?
Original post by Nasa1726
Chlorine displaces iodide ions from potassium iodide. What is the oxidizing agent?
A)Chloride ions
B)Chlorine
C)Iodide ions
D)Iodine
The answer is B .When I came to answer, I knew it was gonna be A or B but how do you choose between both? Also, since the answer is B does that mean ions cannot be oxidizing agents?

Chloride Ions are not one of the reactants in this. Also chloride ions are cl- and to oxidise something they would have to get reduced themselves going from cl(1-) to cl(2-).
Because in the reaction “chlorine” is reduced to form “chloride ions” not the “chloride ions” form “chlorine”unless it’s the reaction with potassium flouride.If it has been about reducing agent then it would have been “iodide ions” because they oxidise to form “iodine”.
I hope this’ll help, I know it’s a bit confusing.
(edited 1 year ago)
an oxidising agent is an electron acceptor. It will oxidise a substance and be itself reduced. Chloride ions cannot act as an oxidising agent since they are formed when a chlorine atom gains an electron, that is it oxidises something- it is acting as an oxidising agent. Chloride ions can only lose electrons and not gain them, that is they can act as reducing agents.

The chlorine will oxidise the iodide ions and form chloride ions and iodine atoms.

https://science-revision.co.uk/halogen_displacement+reactions.html
Reply 4
Thank you all so muchh!

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