What is diffusion current in chemistry?

[də′fyü·zhən ‚kər·ənt] (analytical chemistry) In polarography with a dropping-mercury electrode, the flow that is controled by the rate of diffusion of the active solution species across the concentration gradient produced by the removal of ions or molecule at the electrode surface.

What is meant by drift current?

Overview. Drift current is the electric current caused by particles getting pulled by an electric field. The term is most commonly used in the context of electrons and holes in semiconductors, although the same concept also applies to metals, electrolytes, and so on.

What is drift and diffusion current class 12?

Drift current is the current flow in the diode due to the applied electric field. Diffusion current is the current due to the diffusion of the carriers because of the change in the carrier concentration.

What is drift current and diffusion current in pn junction?

Diffusion and drift In a p-n junction, n-side has excess of electrons and hence electrons diffuse from n-side to p-side. Similarly, holes diffuse from p-side to n-side. Drift is the process of movement of charge carriers due to the net electric field.

What is diffusion current in a pn junction diode?

From the p-side to the n-side. From n-side to the p-side. From the n-side to the p-side if the junction is forward biased and in the opposite direction if it is reverse-biased.

What is electron diffusion?

Diffusion is defined as the random thermal motion of electrons and holes in semiconductors. This is the movement due to diffusion from a high concentration to a lower concentration region.

What is drift current formula?

Drift Current Calculation : The velocity achieved by the charge carriers due to the application of external voltage is referred to as Drift velocity. The drift velocity for the carrier concentration of electrons is. Vn = µnE.

What is diffusion electron?

What is diffusion in chemistry class 9?

The process of movement of a substance (solid, liquid or gas) from the region of higher concentration to the region of lower concentration so as to spread uniformly is called diffusion.

What is diffusion and types of diffusion?

Three types of diffusion are distinguished, viz., molecular, Brownian, and turbulent. Molecular diffusion occurs in gases, liquids, and solids; both diffusion of molecules of extraneous substances (impurities) and self-diffusion are observed. Molecular diffusion occurs as a result of thermal motion of the molecules.

Why diffusion current equals drift current?

Minority carriers that reach the junction are swept across the depletion region due to drift. At equilibrium, the net current (diffusion and drift current) is zero for both electrons and holes because the diffusion current is equal and opposite to the drift current for both carriers.