Question

What is the difference between an electrochemical cell and a voltaic cell? Is there any? If they are different how do each of their electrons flow?

Answer 1

Defination of electrochemical cell: These are the devices in which either electrical energy is converted to chemical energy or chemical energy is converted to electrical energy. Electrochemical cells are of 2 basic types such as

(a) Electrolytic cell

(b) Galvanic cell (or Voltaic cell)

The followings are the differences between an Electrolytic Cell and a Voltaic cell

1. In electrolytic cell chemical energy is produced from electrical energy, where as in voltaic cell electricity is produced from chemical energy.

2. In electrolytic cell, non-spontaneous redox reaction occurs, where as in voltaic cell, spontaneous redox reaction occurs.

3. In electrolytic cell, both electrodes are dipped into same electrolytic solution, where as in voltaic cell reactions occur in separate half cells.

4. In electrolytic cell, no salt bridge is required, whereas in voltaic cell salt bridge is an essential component.

5.In electrolytic cell, anode is +ve electrode and cathode is - ve electrode, where as in voltaic cell anode is - ve electrode and cathode is +ve electrode.

6. In electrolytic cell electrons are supplied by the external source such as a battery, where as in voltaic cell electrons are supplied by the species getting oxidised.

7.In electrolytic cell electrons come out of anode to the battery and then enters into cathode, where as in voltaic cell electron flows from anode to cathode in the external wire.