electrical conductivity of ions

[MDwannabe7]

In studying the different phases and then solubility, I noticed that ionic solids are poor conductors of electricity, but the electrical conductivity of aqueous solutions is governed by the presence and concentration of ions in solution. Is it simply that in aqueous solutions, ions can move around, while they are held in place in the solid state? What makes them poor conductors as compared to metallic solids? Please explain!

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[spyderracing32]

Conductivity has to do with the freedom of electrons to move in whatever phase the matter is in. An ionic solution is full of charged particles free that transport the electrons as a result of their charge. In an ionic solid, the electrons are locked in an ionic lattice and are not free to move. I'm not a chem major so my description of metals is probably going to suck but essentially some electrons (i think it's the d-orbital electrons) are free to flow within the solid. It was described to me (and has stuck for 3 years) as raisins in peanut butter (the raisins being the electrons and the peanut butter being the medium, the metal, in which they move). They are loosely held but in the event of something occurring that would compel them to move (a potential difference in a metal) they can move.

 

[Phlame217]

With metals, remember "sea of electrons"

Metals are both ductile and conductors in part due to the ability of electrons to flow freely between the p orbitals and d orbitals. They, therefore can recieve an electron on the left end which in essence causes an electron on the right end to bump off. Its kinda like those ball stands where when one ball drops, it knocks another up, etc.

Ionic solids have no free electrons, they have their octet and are bonded by overall charge and not covallence. Therefore in solid state, electrons cant be absorbed or lost. For more depth, think of the ionizing energy involved in ionizing a noble gas or Ca2+ etc.... Itll be redicously high.

But when those ions are broken apart and their charges exposed, electrons can freely flow through fluids.