Which metal conducts electricity faster?

The chemistry side


Metal bonds

Properties of metals

  • opaque
  • good electrical and thermal conductors
  • easily deformable
  • all of this is retained even in the liquid state

Electron gas

There is an electron gas in metals. Every metal atom releases its electrons from the outermost shell to this electron gas. The electron gas is responsible for the high electrical conductivity, since the electrons are highly mobile and are delocalized over the entire metal body.

Metals are Electron deficiency systems. There are far fewer electrons than there are molecular orbitals, since each atom has a whole band of molecular orbitals, because the electrons can take any distance from this atom with the help of the other atoms. The electrons can quasi in one Energy band move.

Conductor, semiconductor, insulator

The conductivity of a substance depends on whether it can transport electrons in a conduction band or not.
  • ladder: Metals are good conductors as you Valence band the Conduction band overlaps9. Thus, electrons can be transported through the electron gas. When the temperature rises, these metals are less and less conductive. The electrons start to get faster and faster and also to scatter into the atomic cores, which is why they are no longer present in the conduction band.
  • Intrinsic semiconductors: With self semiconductors that is Valence band although fully occupied, it does not overlap with the conduction band. There is a small one Band gap. However, this can be bridged when it is hot, in that excited electrons jump into the conduction band and thus conduct the current.
  • Isolators: In isolators the valence band and conduction band are too far apart. The band gap is too large, which is why the electric current is not conducted even when it is excited.

Doped semiconductors

Silicon is used in the manufacture of computer chips. This is because silicon is a semiconductor. In its original state, silicon does not conduct electricity. However, foreign atoms can be embedded in the silicon lattice (silicon, like carbon, has four bonds):
  • One can insert an arsenic atom (As). This is one main group higher than silicon and is therefore actually five-bond. It can donate an electron to the grid10because it is relatively easy to remove from the shell. This electron then causes the conduction. Such an atom is called Donor atom and the semiconductor n-semiconductors.
  • You can also insert an indium atom (In). This has one electron less than silicon and therefore gladly takes an electron from silicon11. They arise in the valence band of silicon Defectswhich can also conduct electricity. Such a semiconductor is called p-semiconductor.
High-purity silicon is required to manufacture computer chips. This is obtained by chemically separating the silicon from impurities through a reaction:

is Silicochloroform.