Why more attractive metals will be oxidized? Aren't they being reduced, because they attract and receive electrons from negative polyatomic ions? So they will be anodes, where oxidization occurs. Why anodes are negative in voltaic cells and positive in electrolytic cells? Same for cathodes.
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asked Apr 24, 2014 at 3:35
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Metals want to lose electrons and become positively charged. When the metal loses the electron, it is called oxidation. The substance that gets the electron is reduced.
Oxidation could occur at the anode if it takes electrons from a metal (i.e. $Fe^{2+}$ to $Fe^{3+}$).
Anodes are negative in voltaic cells since there are excessive electrons available to power the circuit. Cathodes give electrons away to the solution.
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$\begingroup$ I saw cation related cathode but cation is positive ion. $\endgroup$ Commented Apr 24, 2014 at 14:57
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$\begingroup$ but then why still anodes are positive in electrolytic cells? in other words, why excessive electrons stay in the cathode of a electrolytic cells? $\endgroup$ Commented Apr 24, 2014 at 15:00
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$\begingroup$ You need to remember that electron flow is the reverse of current flow (someone guessed, he was wrong). Take a moment to think about which way the electrons are moving and what you want to call positive. blog.sciencegeekgirl.com/2009/02/27/… $\endgroup$– LDC3Commented Apr 25, 2014 at 1:23