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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: onlyfknhuman on November 12, 2008, 08:40:08 pm

Title: Galvanic. stav is fucked
Post by: onlyfknhuman on November 12, 2008, 08:40:08 pm
question 6 short answer,

it asks the direction of the electron. which is from anode to cathode, hence zinc to copper it says.

then it askes u to write the equations of teh anode and cathode

the anode was zn -> zn2+ +2e-
and the cathode was 2H++2E- -> H2

the question states, that it produces hydrogen at the cathode.

But why does the answwer to the previous question say that its going from zinc to copper.

-_-'so shuldnt the cathode be a copper half equation
Title: Re: Galvanic. stav is fucked
Post by: roly182 on November 12, 2008, 08:51:10 pm
Copper can still act as a cathode but just not react.. it is just a conductive metal used as an electrode as the surface for the reduction of hydrogen ions
Title: Re: Galvanic. stav is fucked
Post by: ed_saifa on November 12, 2008, 08:54:05 pm
Zn is a stronger reductant than Cu and so will be preferentially oxidised.
Title: Re: Galvanic. stav is fucked
Post by: onlyfknhuman on November 12, 2008, 09:49:11 pm
oh fuck is copper an inert electrode... totally blanked out on that
Title: Re: Galvanic. stav is fucked
Post by: Mao on November 12, 2008, 10:00:35 pm
no, copper is not inert

but Zn is a stronger reductant, and H+ is the strongest oxidant, hence copper in this case doesn't react.