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Galvanic Cells (1 Viewer)

untouchablecuz

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I was revising production of materials and this got me stumped. What is the anode, postive or negative? What is the cathode, negative or positive? Do the electrons flow from anode to cathode or from cathode to anode?

I always thought:

The anode is POSITIVE since it attracts negative anions and because oxidation occurs at the anode (electrons are lost resulting in a deficiency of electrons).

The cathode is NEGATIVE since it attracts positive cations and because reduction occurs at the cathode (electrons are gained resulting in an excess amount of electrons).

Hence the current flows from cathode to anode.

BUT, many websites and textbooks say the complete converse: anode is negative, cathode is positive, current flows from anode to cathode.

Please explainnnnnnnnnnnnn? :cold:

EDIT: Another question, is the voltage greater when the elements acting as the cathode and anode are further apart on the list of standard potentials?
 
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Aerath

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OK, in Galvanic cells, the cathode is positive, whereas the anode is negative. This is the reverse in an electrolytic cell. But here's the way to remember it, reduction always happens at the cathode, whereas oxidation always occurs at the anode (regardless of whether it is a Galvanic or Electrolytic cell.

Why is it different when comparing Galvanic cells to electrolytic cells? Well, in Galvanic cells, you're attempting to turn chemical energy into electrical energy (electrical energy is 'made'), whereas in electrolytic cells, energy is 'supplied'.

Electrons always travel from negative to positive. So in a Galvanic cell, they travel from anode to cathode.
 

bored of sc

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Red Cat: reducation occurs at the cathode.
An Ox: oxidation occurs at the anode.
OIL RIG: oxidation is loss, reduction is gain (of electrons).
 

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