Cathode

What Does Cathode Mean?

A cathode is a negatively charged metal electrode from which
conventional current travels in a polarized electrical device. It attracts positive charge or cations. The behavior
of the cathode is the opposite to that of an anode. In a polarized electrical device, a
cathode is considered the electron donor or the source of electrons.

Advertisements

Techopedia Explains Cathode

A cathode is a negatively charged electrode. However, the
polarity of the cathode with respect to anode can either be negative or
positive, and it largely depends on the operation of the device. For example, in
a recharging battery the cathode is negative. However in the case of discharging
a battery, the cathode polarity is positive.
In general, in a device the cathode is the terminal from which the current
flows out, whereas the anode is the terminal from which the current flows in from
outside.

In chemistry, the cathode is considered as the electrode at which the electrochemical
reduction takes place. The distinction between cathode and anode is purely
based on the current and not on voltage. The metal used for the cathode has a significantly
higher number of electrons than neutrons or protons. In most
applications, the cathode gains mass over
time due to the gain of cations. The electrons
from the cathode repel each other, and thus move away from the cathode,
reaching the anode, which has the
opposite polarity. Thus, cathodes along with anodes occupy important roles in
the production of electrochemical reactions.

Advertisements

Related Terms

Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.