Question

Why does voltage decrease when concentration increases?

Answer 1

Voltaic cell

An electrochemical cell that changes the chemical energy of spontaneous redox reactions into electrical energy is known as a galvanic cell or a voltaic cell.

The voltage decrease as the concentration increases because:

1. An electrochemical cell's voltage differential will increase as the reactant concentration rises.
2. A higher voltage is seen as a result of the faster reaction caused by the reactant's increased concentration, which allows for more forward reactions.
3. If we adjusted the cell volume to keep the total amount of reactants the equal or same, then the rate of electron flow via the cell will be higher at first.
4. Then the cell will run down faster, but the total amount of electron flow will be equal.
5. So, as the concentration rises, the voltage drops because the resistance rises as well, reducing the potential difference and lowering the voltage.

Hence, due to the above-motioned reasons, the voltage decreases when concentration increases.