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(AQA AS Chemistry) Redox reactions - help!

CuCl2 + Zn = Cu + ZnCl2

5H2O2 + 2KMnO4 + 3H2SO4 -> K2SO4 + 2MnSO4 + 8H2O + 5O2

Why are these two reactions redox reactions?

(I thought the first one was a displacement)
A redox reaction means there's electron transfer between 2 things. A displacement reaction is just an example of this; displacement reactions are redox reactions. So you are correct, it's also a redox reaction though.

In your displacement reaction (first reaction), Cu is reduced from +2 to 0, and Zn oxidised from 0 to +2, so it's definitely redox 🙂 hope this helped.

Also, the second reaction is redox as KMnO4 acts as an oxidizing agent, and H2O2 acts as a reducing agent. You can also compare oxidation states here to visualise that. If you want to quickly see oxidation states this website is useful: https://chemequations.com/en/
Reply 2
Original post by dontknowlol
A redox reaction means there's electron transfer between 2 things. A displacement reaction is just an example of this; displacement reactions are redox reactions. So you are correct, it's also a redox reaction though.
In your displacement reaction (first reaction), Cu is reduced from +2 to 0, and Zn oxidised from 0 to +2, so it's definitely redox 🙂 hope this helped.
Also, the second reaction is redox as KMnO4 acts as an oxidizing agent, and H2O2 acts as a reducing agent. You can also compare oxidation states here to visualise that. If you want to quickly see oxidation states this website is useful: https://chemequations.com/en/

This is so helpful, thank you so much!

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