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What is cell potential and emf? Explain representation of galvanic cell with examples?

Vidyadip · Accepted Answer

→ "The potential difference between the two electrodes of a galvanic cell is called the cell potential and it is measured in volts."
→ The cell potential is the difference between the electrode potentials (reduction potentials) of the cathode and anode. It is called the cell electromotive force (EMF) of the cell when no current is drawn through the cell.
$\begin{array}{l} E _{\text {cell }}= E _{\text {right }}- E _{\text {left }} Or \\ E _{\text {cell }}= E _{\text {red(cathode) }}- E _{\text {red(anode) }}\end{array}$
Cell Representation:
→ We keep the anode on the left and the cathode on the right while representing the galvanic cell.
→ A glavanic cell is generally represented by putting a vertical line between metal and electrolyte solution and putting a double vertical line between the two electrolytes connected by a salt bridge
Anode half cell || cathode half cell
Example :
Cell reaction :
$
Cu ( s )+2 Ag ^{+}( aq ) \rightarrow Cu ^{2+}( aq )+2 Ag ( s )
$
Half-cell reaction :
Cathode (reduction) : $2 Ag ^{+}( aq )+2 e ^{-} \rightarrow 2 Ag ( s )$
Anode (oxidation) : $Cu ( s ) \rightarrow Cu ^{2+}( aq )+2 e ^{-}$
→ Silver electrode acts as a cathode and copper electrode acts as an anode. The cell can be represented as :
$Cu ( s )\left| Cu ^{2+}( aq ) \| Ag ^{+}( aq )\right| Ag ( s )$and we have $E _{\text {cell }}= E _{\text {right }}- E _{\text {left }}= E _{ Ag ^{+} \mid Ag }- E _{ Cu ^2 \mid Cu }$

Example	Magnatic Moment (BM)
K₄[Mn(CN)₆]	2.2
[Fe(H₂O)₆]²⁺	5.3
K₂[MnCl₄]	5.9

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