Electrochemistry | Electrode Potential | Cells | A level Chemistry | Question Walkthrough 1
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- เผยแพร่เมื่อ 20 มิ.ย. 2022
- Electrochemistry
Electrode Potentials
Electrochemical Cells.
Exam Question Walkthrough.
Question download:
drive.google.com/file/d/1N7eg...
A level Chemistry.
i'm just going to say i am amazed at how well you explained the last question. Both my teacher were not able to. Your videos are really helping mt to cement my knowledge. Hope more people can discover your channel.
Thank you! That's a really lovely thing to say. I'm really glad they are so useful! Best of luck tomorrow 👍
This guy has carried me through the last week of chemistry exams
onggg
You've nearly made it 🙌
Good luck
you explain the questions really well, tysm for the help
You're very kind, thank you 😊
you have saved my chemistry paper 3
That's very nice of you to say! I'm sure you'll be great tomorrow 👍
If the question said, write a half equation for the reduction process occurring at the positive electrode would you start with the Fe3+ and then go to the Fe2+ and balance the no. of electrons and charges?
Yes that's right.
UNLESS the reducing agent was powerful enough and able to turn Fe2+ into Fe.
You'd have to double check that from the electrochemical series
Is it always that if equilibrium shifts to the right EMF increase and if it shifts to the left it decreases.
Not quite. If a half cells equilibrium shifts right, then its electrode potential will increase, and a shift left decreases it.
The effect this has on the emf can only be determined if you know whether you've increased the larger E value (so the EMF increases) or the smaller E value (which would reduce the EMF
hi ! for a)i) how do you know which half equation to write? i got taught that the reaction happens on the left on the cell presentation was for the oxidation reaction which would be at the positive electrode? thanks :))
Oxidation happens at the negative Electrode. It's the one with the smaller E value
and so the reaction goes backwards and produces electrons. (Another reason why it's negative)
@@chemistrytutor oh i see ! thank you so much !! the video helps a lot !!
Idk if you will see this before my exam tomorrow. But can you dumb it down for me and explain what the positive and negative electrodes are? Isn't the negative electrode where reduction occurs?
The negative Electrode is the one with the smaller E value.
So whatever the numbers are, the smallest of the pair will be the negative Electrode. And that's where oxidation happens.
That's because it's where the reaction moves to the left and loses electrons.
The larger E value equation, moves to the right and gains electrons so is reduced. This is the positive Electrode
with Q B iii is the answer that because its doubled on both sides or just because surface area has no effect
Surface area doesn't have any affect at all 😀
idk why but that last question was mind blowing, I would never have thought of that haha
Hey, that's why we do practice questions 😃
Good luck 👍
@@chemistrytutor thank you!!
last minute revision after that surprise electrode potentials in paper 1, need to make up for it in paper3
Good luck tomorrow!
@@chemistrytutor literally 1 question and it was 3 marks
@@alaabenrahuma7660 that's so cheeky! Hardly a major focus!! Its over now though, well done!
Hi, do you know where I can find more practical 4 exam Qs?
Isnt that just tests for anions,cations and halides?
@@darkhacker8747 yeah but can’t really find any questions on it other than the ones on the prac 4 video he posted
@@haseeb_lds788 Well the tests for the halide ions will be in group 7 and will also be in organic analysis so mostly throughout paper 1. Same with the tests for acids and aldehydes/ketones etc. I recommend going through all the paper 3s as exam practise if u havent already cuz thats the best thing you could do to get more examples. Also the MCQ in paper 3 have a few where they test ur practical 4 knowledge.
I think this is good advice. There aren't tonnes of examples of long questions about this. It's bits here and there, and multiple choice questions
Please could you do a revision video on electrochemical cells? Thank you.
This is in the pipeline 😀
@@chemistrytutor thank you very much for your reply thanks for your efforts.
@@antipsikiyatriKizi 😀
@@chemistrytutoris this video out I really struggling with this topic?
legend
Thanks 😊
Can you do halogenoalkanes if possible
I made it earlier this morning. TH-cam should have finished processing it by lunchtime 😃
is there a second video?
There isn't a second electrochemistry video yet. It's on my list though.
If there is something specific you're interested in please let me know 😊
@@chemistrytutor fuel and battery cells, standard hydrogen electrode and another hard one like the VO2+ question in this video please
There is now!
th-cam.com/video/tRy5ppH9zSQ/w-d-xo.html
@@jclxo5095 here you go...
th-cam.com/video/tRy5ppH9zSQ/w-d-xo.html
i dont think question b)iv) is in the spec any more
Hi thanks for the comment. I dont think it has been totally removed actually. Something called the Nernst equation has been (you used to have to do calculations around changing E values) but most specs say something like
"Students should know the importance of conditions when measuring Electrode potential"
And whilst that doesn't mean literally that you have to answer this type of question, it would mean that it is fair game.
I agree it's not come up recently though
@@chemistrytutor thank you, i suppose its best to be aware of it.
@@guscox9651 agreed 👍
Is this same guy as allery chemistry sounds very similar
A different guy 😎
Hope your exams went well