Sodium Chloride & Electricity

[sas123]

A question that i'm stuck with is ' explain why sodium chloride conducts electricity in the molten state but not when it's a solid'. please could you help me!

also, what are 2 properties of metal which are caused by the displaced sea of electrons that is metallic bonding?

[firebird]

Originally Posted by sas123

A question that i'm stuck with is ' explain why sodium chloride conducts electricity in the molten state but not when it's a solid'. please could you help me!

The sodium ions and chloride ions in the solid are tightly held in a lattice/crystal structure. To carry electricity they need to be able to move along in a particular direction. They can do this in the molten state.

[KathChem82]

when NaCl is put into water it dissociates into its ionic forms, Na+ and Cl-. these ions allows the flow of electricity on your solution. thus conductivity occurs.

[heidi]

Originally Posted by KathChem82

when NaCl is put into water it dissociates into its ionic forms, Na+ and Cl-. these ions allows the flow of electricity on your solution. thus conductivity occurs.

Note/ The question wasn't about dissolving in water, it was about molten NaCl.

Metals are different from ionic substances because, even when metals are solid, they still have free electrons floating around to carry electricity.

In ionic solids, electrons aren't free to move around. In ionic solids, its the whole atom (more correctly the whole ion, which is an atom minus or plus an electron or two) that needs to move to carry electricity and this can only happen if the ionic solid is melted, or like KathChem said, dissolived in a liquid.