All Questions
32
questions
15
votes
7
answers
111k
views
Which is anode and which is cathode?
A maybe (hopefully) simple question about the denotations of "anode" and "cathode". The below image is a schematic of a polymer solar cell (Source (WBM)). (The figure text is quoted as well for the ...
- 930
1
vote
1
answer
2k
views
Difficulty understanding redox in terms of hydrogen and oxygen transfer?
I have come across 4 ways of defining oxidation:
loss of electrons
increase in oxidation number
gain of oxygen
loss of hydrogen
From these definitions, I have an idea of what I think 'oxidation' and ...
- 1,697
0
votes
1
answer
982
views
Why does oxidation of the electrode take place in a solution?
What makes the electrode atoms start to ionize? Perhaps because of the solutes in the solvent?
So probably if you place it in distilled water it will not ionize, right?
Follow up question: If the ...
- 329
5
votes
1
answer
3k
views
In a galvanic cell where the two electrodes are in the same electrolyte solution, why do reduction and oxidation occur separately?
In a certain book, I was presented with the following solution:
An iron nail is attached by a piece of wire to a magnesium ribbon, and the iron and magnesium are placed into the same container, with ...
- 51
5
votes
1
answer
6k
views
Current in a galvanic cell
I was looking through chemistry textbooks to find out how to determine how much current a galvanic cell should generate and what affects that current value. However, I did not find anything: textbooks ...
- 864
2
votes
1
answer
2k
views
Why can't electrons be transferred using hydrogen ions?
Recognizing how oxidation and reduction occurs is essential for analyzing and understanding biochemical reactions. Which of the following methods would NOT be employed in transferring electrons in ...
- 443
4
votes
2
answers
5k
views
Why Fe 3+ is more common than Fe 2+
I heard that $\ce{Fe}(\mathrm{III})$ is more common than $\ce{Fe}(\mathrm{II})$ but I've not heard a very clear explanation. Could someone please explain this incorporating electron configurations in ...
- 149
1
vote
1
answer
17k
views
Determining number of electrons transferred
When determining the number of electrons transferred in a redox reaction is it the total in both half equations?
For example:
$$\ce{2I- + Zn^2+ -> I2 + Zn}$$
First we split it up into the two ...
- 25
-3
votes
1
answer
254
views
What is the purpose of the solution in a galvanic cell?
In other words: What is the purpose of the solution that the electrodes are immersed in, in a galvanic cell, and is it possible to generate a current without any solution?
2
votes
1
answer
2k
views
The anode and cathode when corrosion happens
Let's say $\ce{Fe}$ reacts with $\ce{Cu^{2+}}$ ions. $\ce{Fe}$ would oxidize and therefore give electrons to $\ce{Cu^{2+}}$so that:
$$\ce{Fe-> Fe^{2+} +2e-}$$
$$\ce{Cu^{2+} +2e^- ->Cu}$$
The ...
10
votes
3
answers
13k
views
Why is chloride oxidised instead of water in copper chloride electrolysis?
For the Electrolysis of Copper Chloride:
Cathode: $\ce{Cu^{2+} + 2e- <=> Cu}$
Anode: $\ce{2Cl <=> Cl2 + 2e- }$
I am confused about the reaction taking place at the anode. Wouldn't $\ce{...
- 231
3
votes
1
answer
356
views
Balancing redox equation
So I had these two reactions that confused me .. I tried the standard way of balancing it (Putting oxygen number everywhere, +1,+2,-2 etc.) and then go on with it but it didn't work
So anyways here ...
- 31
5
votes
2
answers
22k
views
Explanation for the reactions in a saltwater battery with zinc and copper electrodes
I am a physicist, not a chemist. I'm trying to get a basic understanding of the reactions taking place in a battery using a saltwater electrolyte with copper and zinc terminals. I'm writing a general ...
- 151
7
votes
1
answer
392
views
Prediction of ionic reduction?
Here are some standard electrode potentials:-
$$\ce{SO_4^{2-} + 4H^+ + 2e^- -> SO_2 + 2H_2O}\\E^o=0.17\mathrm{V}\\
\ce{NO_3^- + 4H^+ + 3e^- -> NO + 2H_2O}\\E^o=0.97\mathrm{V}\\
\ce{NO_3^- + ...
- 6,795
3
votes
1
answer
2k
views
Electrode potentials at interfaces?
My questions relates to the fundamental concept of electrochemistry, more specifically the electrode potentials.
1) First, why is there a potential difference at the interface of two phases? ...
- 6,795