A hot cathode is one that is heated in the presence of a filament to emit the electrons by thermionic emission. In X-ray tubes and, electron guns, the part that emits electrons into the device forms the cathode.Ī cathode can be a hot cathode or a cold cathode. The cathode attracts cations and oxidizes them in electrolytic and galvanic cells. In this case, an electric current is leaving from the negative terminal of the battery so it (negative terminal) will act as a cathode. Since the current is leaving from the positive terminal of the battery, it (positive terminal) will act as a cathode during the discharging conditionĭuring charging condition electric current flows from the negative terminal of the battery to the positive terminal of the battery. Just like anode, there is no particular polarity of a cathode, it also depends on the type of cell being used.ĭuring discharging of a battery or, when an external load is connected to the battery, the electric current flows from the positive terminal of the battery to the negative terminal of the battery. It is the electrode at which a reduction reaction takes place. Since the direction of flow of electrons is opposite to the direction of the current, we can say that a cathode is an electrode that has the flow of negatively charged electrons entering into it. What is cathode?Ī cathode is an electrode from where the current flows out of the device. The sacrificial anode which we have used will absorb all the static charge and slowly gets disintegrated. This method is common in ships where a static charge is created due to the flow of water. In the sacrificial anode coating, zinc is used to protect metals.

It is not mandatory that cathode and anode will always be used together, there are applications where anode alone is used. And the side where we will connect the negative terminal will be the cathode. In the case of capacitors and diodes, the anode is that side where we connect the positive terminal, this is because current will enter from this side. So in this case, the anode will be the positive terminal of the battery. So in this case anode will be the negative terminal because electricity flows into the negative terminal.ĭuring charging of the battery, the electricity flows from the negative terminal of the battery to the positive terminal of the battery. We can’t define an anode as positive or negative because its polarity depends upon the type of cell being used.ĭuring discharging of a battery or we may say that when a load is connected to the battery, the electricity flows from the positive terminal of the battery to the negative terminal of the battery. An anode is a terminal where current flows into a device from the outside.

It can also be defined as the electrode from which the current enters into the polarized electrical device. The electrode at which oxidation reaction takes place is known as the anode. The anode attracts anions in an electrolytic cell.Ĭathode attracts cations in an electrolytic cell. Polarity of the terminals in a galvanic cell Polarity of the terminals in an electrolytic cell Reduction reaction occurs at the cathode. Oxidation reaction takes place at the anode. Type of reaction taking place at the electrode Let’s see the key differences between anode and cathode through the following table. It is an eminent component of an electrochemical cell that remains in contact with the electrolyte. An electrode is a substance that helps in the conduction of electricity wherein the current enters or leaves the non-metallic medium like an electrolyte. Before learning about anode and cathode we need to understand what an electrode is.

Cathode anode diagram