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What voltage would have been observed if you had switched the position of the electrodes but not the solutions for any of the electrochemical cells

User Myforwik
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This question is incomplete, the complete question is;

An electrochemistry lab was conducted. What voltage would have been observed if you had switched the position of the electrodes but not the solutions for any of the electrochemical cells? (e.g. placed Cu electrode with Zn²+ and Zn with Cu²+).

Clearly explain your answer, include what would have happened in each cell

Answer:

E°cell = +1.10V

Step-by-step explanation:

At lower reduction potential, electrode acts as an anode ( -ve )

At higher reduction potential, electrode acts as a cathode ( +ve )

NOW

standard reduction of Cu⁺² / Cu electrode,

E° cu⁺²/cu = 0.34V

standard reduction potential of zn⁺² / zn electrode,

E° zn⁺/zn = -0.76V

Zn has lower reduction potential, therefore it acts as an anode and standard reduction potential of Cu has higher reduction potential so it acts as a cathode.

now we know that

E°cell = E°cathode - E°anode

we substitute

E°cell = 0.34V - ( -0.76V)

E°cell = +1.10V

Therefore there is no flow of e- in the wire when the copper electrode placed in Zn²⁺ ( electrode reverse). When zinc electrode placed in copper solution, copper deposition in zinc electrode takes place, so zinc is converted into Zn ion and no flow of e- will occur in outer circuit.

∴ The voltage becomes zero

User Bobbymcr
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