I am really confused simply on the way this question is worded - can someone please explain to me how I may be able to view this in a constructive easy way?
I understand the initial redox numbers but the second half of the problem confuses me…
So on the negative plate, oxidation has to occur and this electrolysis reaction is a redox reaction. (reduction happens on the positive plate as you have correctly identified) The lead on the lead plate plate becomes oxidised as electrons are donated.
Pb → Pb2+
Hope this helps!
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Hey Ujjwal!
Isnt cathode negatively charged to attract cations, and anode positively charged to attract anions? So on cathode, reduction of cations will occur while on the anode, oxidation of anions?
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Hi Darius thanks for pointing it out i mistakenly wrote it opposite it should be negative cathode and the positive anode and yes at the Anode we have oxidation while at cathode reduction takes place.
I edited my solution, Does it make sense now??
Hope it helps:)
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Hi!
This question is pretty confusing i got confused in my own reasoning eventually i got it
Well they have given us a battery and we know it has a +ve and a -Ve terminal the cathode is one connected to the positive terminal so lets consider it the positive plate and the Anode as the negative one.
ATQ, on charging the +ve plate is covered with Pbo2 which on discharging got converted to pbso4 so there’s a change in oxidation state from +4---->+2 so clearly at cathode we have reduction.
On charging the -Ve plate i.e the Anode it remains Pb but on discharging it gets covered with Pbso4 so a change in oxidation state of 0----->+2 clearly oxidation taking place at Anode.
so, our answer option is B positive plate(cathode) +4 to +2 and negative plate (Anode) 0 to 2.
Does it make sense now? kindly review the solution and let me know if there’s any mistake.
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@AriHoresh would it be possible to help us all with the question and clarify. I am thoroughly lost.
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Hey! The problem is just talking about oxidation numbers.
It’s saying that at first we have only lead, which is finally converted into PbSO4 (change of O.N from 0 to +2) (This happens in the NEGATIVE PLATE)
On the other hand, we have PbO2, which finally converted into PbSO4 as well (change of O.N from +4 to +2) (This happens in the POSITIVE PLATE)
Therefore, we have oxidation in the negative plate, and reduction in the positive plate. Hope this helps! 
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It is so simple its hard! haha - thank you!
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Thanks to you! I’m glad it was helpful.
Hello, I want to ask, so this is the rule, right? I mean in any case this always happens as “oxidation in the negative plate, and reduction in the positive plate”?
Thank you so much!
hello! In Electrolysis is actually the opposite, that’s why this question is quite tricky.
In Electrolysis, reduction happens in the cathode (negative plate) and oxidation in the anode (positive plate). The nmemotechnia I use is “angry red cat” (red-> reduction. Cat-> cathode. and “angry” because it’s negative 
)
This question doesnt mention that it is electrolysis, so we can’t infer that it is. The trick here is to figure out if it was reduction or oxidation based on how the O.N’s changed.
Hope this is useful! .
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Hi, thank for answering me, it’s really helpful!
Can I ask one more question, how do we know this question is electrolysis? :((( Is there any key that show this is electrolysis?
Thank you so much again!!!
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hey! This question is not electrolysis When it’s electrolysis they mention it directly
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Ah I see, sorry my bad. But thank you so much! It’s really helpful!!!
Hello, I’m sorry for bothering you but after rereading, I still don’t understand your explanation. :((( So in this question, why do you know PbSO4 (change of O.N from 0 to +2) happens in the NEGATIVE PLATE? And the vice versa?
I’m sorry for asking too much.
Thank you very much!!!
It oxidises because it donates electrons to the negative plate. They call it the negative plate (the anode) but it is actually positively charged. Oxidation happens at the anode.
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ohhh nono please dont be sorry 
You dont bother me at all, dont say that, okay? Im sorry for the late reply, I had a really busy day.
Its totally okay to be confused since this question is quite tricky 
okay so , as we know:
NEGATIVE PLATE: only lead, which is converted into PbSO4 (hence, there’s a change of its O.N from 0 to +2) (OXIDATION)
POSITIVE PLATE: PbO2 is converted into PbSO4 (change of O.N from +4 to +2) (REDUCTION)
What I mentioned in the previous comments was that the tricky part about this question is that we could easily confuse this experiment with electrolysis (it is not electrolysis because it is not specified). But why could be this confusing? Because in electrolysis happens the opposite 
:
In Electrolysis, reduction happens in the negative side, and oxidation in the positive side.
Hope this makes things clear🥺 Please dont doubt to ask anything else if you still dont understand🔅
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Hi, sorry for replying late, I understood your explanation!!! You’re so nice Thank you very much!!! I hope you have a great day!
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