A battery stores no electricity as such; it stores two metals with different appetites for electrons, plus a path that makes those electrons take the long way round through the wire. Zn as the anode paired with Cu as the cathode gives an EMF of exactly 1.10 V, the Daniell cell, because the standard reduction potentials differ by 0.34 minus −0.76. The salt bridge looks like a minor accessory yet it is the vital piece: without it charge piles up on both sides, positive ions accumulating in the anode beaker and negative ions in the cathode beaker, and the cell dies almost instantly even though both metal strips still sit in solution.
A battery stores no electricity as such; it stores two metals with different appetites for electrons, plus a path that makes those electrons take the long way round through the wire. Zn as the anode paired with Cu as the cathode gives an EMF of exactly 1.10 V, the Daniell cell, because the standard reduction potentials differ by 0.34 minus −0.76. The salt bridge looks like a minor accessory yet it is the vital piece: without it charge piles up on both sides, positive ions accumulating in the anode beaker and negative ions in the cathode beaker, and the cell dies almost instantly even though both metal strips still sit in solution.
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