Why do Metals conduct electricity?
Metals are considered as good conductors of electricity. In terms of chemistry, a metal is a chemical substance that can generate positive ions in solution. This means that metals tend to lose more electrons and metal oxides form basic solutions in water. Metals are called as solids that are crystalline in nature. The atoms in the metal will be closely and tightly packed and several atoms are present in a very small space. The chemical bonding observed in the metals is called specially as metallic bonding.
In a crystal of the metal the tightly arranged ions are surrounded by a group of free valence electrons. The free electrons are not restricted to any particular ion and they keep moving from one ion to another. Due to the presence of free electrons, metals act as good reflectors of light. Metals have the capacity to reflect about ninety percent of light that falls on it. The free electrons will not absorb light instantly or transmit it. When we observe the electrical and heat conductivity of metals and other substances, there is a huge difference.
The electrolytes in the batteries conduct electricity about one millionth as that of metallic conductors. Non-electrolytes and non-metals conduct electricity less than one-trillionth of that of good conductors in metals. Metals conduct heat and electricity with the help of free electrons in them. When the voltage is applied across the metal, electrons are made to move towards the positive side of the metal. The flow of free electrons will be negligibly resisted and a large flow of electrons takes place. This flow of electrons is called as passage of electric current. Conduction of heat through the metal is also transfer of kinetic energy by the free electrons.
Since the electrons in the metal that aid in conducting electricity are delocalized electrons, the electron cloud will not be possessed by any one of the atoms. When a current is passed at one side of the metal, the loosely held electrons in the metal transmit the current to the other end very efficiently. The resistance will be less if the electron clouds are loosely held and hence conduction of electric current will be more. In non-conductors there will not be electrons that are free and the electrons are held by the atoms tightly. High energy is required to drag the electrons from the Orbitals in non-metals and therefore they have high resistance for current passage.