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Can somebody help me with this? - Question on observed changes Topic 3 periodicity

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I'm studying for the May exams that are in a week. Been doing the May 2014 past paper 2 (TZ1) and I've come along this question:

 

Chlorine gas, Cl2(g), is bubbled through separate solutions of aqueous bromine, Br2(aq), and potassium bromide, KBr(aq).

Predict any changes that may be observed in each case.

(i) Br2(aq):

(ii) KBr(aq):

Any explanation would be highly appreciated! :)

Edited by Baller97

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(i) I don't know what would happen for this one. I want to say nothing would happen though..but I haven't learned diatomic gas reactions. Sorry :(

 

(ii) For this one, chlorine is more reactive than bromine (higher up on the Periodic table) therefore it would displace the Bromine ion and become 

 

Cl2(g) + 2 KBr(aq) --> 2 KCl + Br2(g)

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(i) I don't know what would happen for this one. I want to say nothing would happen though..but I haven't learned diatomic gas reactions. Sorry :(

 

(ii) For this one, chlorine is more reactive than bromine (higher up on the Periodic table) therefore it would displace the Bromine ion and become 

 

Cl2(g) + 2 KBr(aq) --> 2 KCl + Br2(g)

Well the markscheme sais:

(i) Br2: No change

(ii) KBr: Colour change/ from colourless to red/yellow/orange/brown;

 

I just want an explanation for dat ^ :P

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Chlorine gas won't react with bromine. It wouldn't produce a stable product or anything that would favor a reaction occurring. This is why there is no change.

Chlorine gas will, however, react with KBr for the reasons that IbTrojan gave. This produces Br2. KBr is a colorless liquid. Liquid bromine is brownish yellow. Because we're producing bromine, we see the color change.

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Yeah, I was going to mention the color change but I wasn't sure if that happened if you added another halogen to a compound with Bromine in it. Didn't realize it worked both ways. 

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