electrochemical cells (1 Viewer)

[abdooooo!!!]

Originally posted by Xayma
Anode is defined as the terminal at which oxidation occurs. Hence it doesnt matter what charge it is, as long as oxidation of the ions in the solution occurs at that terminal.

nah man, anode is defined as where anions migrate to... but you can also use that definition anode is which oxidation occurs because oxidation is the loss of electrons ie becoming positively charged, hence attracting anions.

 

[Xayma]

Originally posted by abdooooo!!!
nah man, anode is defined as where anions migrate to...

Then why is the anode in a galvanic cell negative wouldnt it repel the anions.

 

[abdooooo!!!]

you see thats the confusion... its not the actual electrodes that is defined negative... its the terminal at which they are connected to, in this case the negative terminal of the voltmeter if you're talking about galvanic cell.

 

[Xayma]

Yeah I know that, Im just going off my textbooks definition.

 

[abdooooo!!!]

well i've drawn up a diagram... i kinda realize the confusion. as you can see its just the end at which the electrode is connected that defines it being negative end or positive end. anode its self will always positively charged while cathode will always be negatively charged.

 

[Xayma]

Originally posted by abdooooo!!!
well i've drawn up a diagram... i kinda realize the confusion. as you can see its just the end at which the electrode is connected that defines it being negative end or positive end. anode its self will always positively charged while cathode will always be negatively charged.

Why do you have electrons travelling from positive to negative? The electrons flow from negative to positive, conventional current flows positive to negative.

 

[abdooooo!!!]

i know... this is not physics. i repeat this is not physics. the positive and negative on the diagram does not actually denote the potential difference of the two. the potential difference would be the other way around if you wanted to show it. all it is suggesting is that... oxidation has made the anode positively charged while the electrons traveled through the wire has made that side of the voltmeter negatively charged.

 

[abdooooo!!!]

ok then i'll make a new one if that diagram does not seem clear enough.

 

[abdooooo!!!]

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[abdooooo!!!]

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[Xayma]

Originally posted by abdooooo!!!
the word anode is derived from an-ions (meaning negatively charged ions)

Just one thing I have to point out cause Im in that type of mood: Anode was presented in the paper before anion (they were both coined in the same paper)
and anode is the negative end because it is the start of electron travel and was refered to as the negative extremity in the original paper. Determining the positive or negative end by which end it hooks up to is pretty much useless, as it isnt always hooked up to a direction dependent circuit (it could be hooked up to a element to heat it up etc.)

 

[abdooooo!!!]

Originally posted by Xayma
Just one thing I have to point out cause Im in that type of mood: Anode was presented in the paper before anion (they were both coined in the same paper)

really? what paper is this... interesting... then i guess my understanding is a little flawed.

Originally posted by Xayma
and anode is the negative end because it is the start of electron travel and was refered to as the negative extremity in the original paper. Determining the positive or negative end by which end it hooks up to is pretty much useless, as it isnt always hooked up to a direction dependent circuit (it could be hooked up to a element to heat it up etc.)

yeah, thats my understanding too but when i realised the misunderstanding that people was having i thought it would be much easier to not point this out. its confusing as it already is... if you try to apply that the same logics to electrolysis cell it just wouldn't work. so my explaination is purely just for determining why electrolytic cell is opposite to galvanic cell in turns of why anode is differently charged.

hey you seem to understand these things pretty well although it is not needed for hsc... are you heaps into chem?

 

[Xayma]

Originally posted by abdooooo!!!
really? what paper is this... interesting... then i guess my understanding is a little flawed.

Faradays paper on the galvanic cell (1834) http://dbhs.wvusd.k12.ca.us/Chem-History/Faraday-electrochem.html

Originally posted by abdooooo!!!
hey you seem to understand these things pretty well although it is not needed for hsc... are you heaps into chem?

Interested in it. I like to know more then I need to because then I can reason out what I need to know if I forget that plus being interested in it helps.

 

[abdooooo!!!]

Originally posted by Xayma
Interested in it. I like to know more then I need to because then I can reason out what I need to know if I forget that plus being interested in it helps.

nah, knowing more actually does a lot of harm to your chances of obtaining a good hsc mark. seriously man... its not how much you know or even more importantly how well you understand, but rather, its about how well you can bullshit according to strict boundaries of the so called hsc chemistry stage 6 syllabus... if you go over that boundary in your answers you are surely destined to end up with a not so pleasing hsc result, well thats what think anyway.

hey what other subjects you do... i think we got common interest. what are you're main interest? the fact that you're reading faraday's paper means that you're interested in electricity.

 

[Xayma]

Originally posted by abdooooo!!!
nah, knowing more actually does a lot of harm to your chances of obtaining a good hsc mark. seriously man... its not how much you know or even more importantly how well you understand, but rather, its about how well you can bullshit according to strict boundaries of the so called hsc chemistry stage 6 syllabus... if you go over that boundary in your answers you are surely destined to end up with a not so pleasing hsc result, well thats what think anyway.

I know how to restrict myself, in the first assesment, I just reguritated the same 3 bits of information about 3 times each ended up with 100% so Im happy.

 

[mazza_728]

10000000000000000000000000000000000000 x infinety
more confused. Im just gonna remember anode = oxidation, cathode = reduction . is this right? ive even forgotten this now

 

[Xayma]

Originally posted by mazza_728
Im just gonna remember anode = oxidation, cathode = reduction . is this right? ive even forgotten this now

Yep anode=oxidation, cathode reduction. In a galvanic Cell (one generating electricity) anode is negative, cathode positive and use different metals/alloys for electrodes. In a electroyltic cell (one using electricity) inert electrodes are used, the anode is positive, cathode is negative.

 

[abdooooo!!!]

Originally posted by Xayma
Yep anode=oxidation, cathode reduction. In a galvanic Cell (one generating electricity) anode is negative, cathode positive and use different metals/alloys for electrodes. In a electroyltic cell (one using electricity) inert electrodes are used, the anode is positive, cathode is negative.

yeah... if you seriously don't get it just remember what is said above

but im not sure why you said inert electrodes should be used... unless you are talking about electrolysis for a specific purpose, ie 2NaCl(aq) + 2H2O(l) ---> Cl2(g)+ H2(g)+ 2NaOH(aq).

im not gonna try to explain anymore... might confuse more lol.