what is difference b/w electrical ,electronic, and ionic conductivity?

Answer 1

Electrical conductivity happens in materials known as conductors, usually metals. The atoms of metals have one to three electrons in their outer shells. When the metal is in a solid state these outer electrons can freely move from atom to atom. When a charge is applied to one side of a lump of metal its electrons move easily in response, away if it is negative and towards if it is positive. Make a wire out of the metal and apply a steady supply of electrons at one end and you get a current through the wire.

Ionic conductivity occurs in solutions of various salts (also in melted salts.) When an ionic compound (salt) is formed the electrons from the metallic atoms are captured by the atoms of the non metal. For example in sodium chloride, the sodium atoms give up their single outer electron becoming positive sodium ions and the chlorine atoms capture those electrons becoming negative chlorine ions. In the solid state the positive and negative ions are held together by their opposite charges in a rigid lattice. In the liquid state (solution or melted) the ions move around freely. If positive and negative electrodes are inserted into an ionic liquid the positive ions will migrate towards the negative pole and the negative ions will move towards the positive pole. At the negative pole, positive ions capture electrons. At the positive pole negative ions give up their extra electrons. Each ion is changed chemically in some way. The movement of charged ions in the liquid is ionic conduction.

Electronic conductivity comes in two forms. Vacuum tube and semiconductor.

A vacuum tube consists of a sealed (glass) bulb with the air pumped out. There are two electrodes inside with connections through the wall. One electrode can be heated to a high temperature usually by having a heating filament near it. When the electrode gets hot enough electrons will be expelled from the metal surface and they will hover around that surface like a tiny atmosphere. They won't go far because the electrode is now positive having lost those electrodes. If you now connect this heated electrode up to a negative source and the other, cold, electrode up to a positive source the electrons will flow across the vacuum from the hot electrode to the cold one. This device is called a diode. Negative current will flow from the hot pole to the cold one but not in the opposite direction. The diode is a one way valve. Other types of electronic tubes have additional electrodes formed as screens between the hot and cold poles. These can be charged in ways that control the flow of electrons through the vacuum. Electronic tubes such as this were the basis of all electronics (radios, TVs, amps, radar, etc) until the invention of the transistor.

The transistor is based on the other kind of electronic conduction. This is dependent on certain elements known as semiconductors. These elements tend to have more electrons in their outer shells than metals but not as many as nonmetals. The outer electrons are held more closely to their parent atoms and so currents don't flow as easily as in a metal. This property can be altered by adding impurities to the basic element. This disturbs the orderly arrangement of atoms and electrons and leaves empty spaces in the lattice which act as positive "holes". When a negative charge is introduced to one side the holes seem to migrate towards it. In fact electrons are moving away from the charge to fill the holes. Each time an electron fills a hole it leaves a hole behind so the net effect is that the hole has move in the opposite direction. Transistors are built by layering different kinds of semiconductors together and applying different charges to each layer. Transistors can do everything that the old electron tube could and some other things besides. Most importantly they can be made very small and they don't use a lot of energy to operate.

Answer 2

electric powered is that branch which bargains with technology and transmission of electrical energy to run quite some machines and equipments. even as electronics bargains with microchips etc specially television radio pc pc are electronics instruments. Fan motor are electric powered instruments. For r and d electronics is sturdy.

Answer 3

ionic conductivity decreases with increase of pressure and the electronic conductivity increases with application of pressure.