Voltaic Cell:
A voltaic cell, also known as a galvanic cell, is an electrochemical cell that converts chemical energy into electrical energy. It consists of two different metals, called electrodes, which are immersed in separate electrolyte solutions. The two electrodes are connected by a wire, allowing the flow of electrons from one electrode to the other.

Zinc and Copper Plates:
In a voltaic cell, the two electrodes are typically made of different metals. In this case, zinc and copper plates are used as the electrodes. Zinc (Zn) is the metal used for the anode, which is the negative electrode, while copper (Cu) is used for the cathode, which is the positive electrode.

Dipping in Separate Solutions:
The zinc and copper plates are dipped in separate solutions to create a potential difference between the two electrodes. These solutions, known as electrolytes, contain ions that can participate in the electrochemical reactions. The electrolyte for the zinc electrode is usually a solution of zinc sulfate (ZnSO4), while the electrolyte for the copper electrode is typically a solution of copper sulfate (CuSO4).

Electrochemical Reactions:
When the zinc and copper plates are immersed in their respective electrolyte solutions, electrochemical reactions occur at each electrode. At the zinc electrode, zinc atoms lose electrons and are oxidized to form zinc ions (Zn2+):
Zn(s) → Zn2+(aq) + 2e-

These electrons flow through the wire to the copper electrode, where copper ions (Cu2+) in the electrolyte solution gain electrons and are reduced to form copper atoms:
Cu2+(aq) + 2e- → Cu(s)

This flow of electrons constitutes an electric current, which can be used to power external devices connected to the voltaic cell. The overall reaction for the voltaic cell is the sum of the individual reactions at each electrode.

Conclusion:
In conclusion, zinc and copper plates are dipped in separate solutions in a voltaic cell. This arrangement allows for the generation of an electric current through the electrochemical reactions that occur at each electrode. The zinc plate serves as the anode, while the copper plate serves as the cathode.