Is salt a good conducter for electricity?

Answer 1

Table salt in the normal dry form of salt crystals has a very low electrical conductivity and is classified as an insulator. Depending on the purity and extent to which water may be present, it would normally be found that salt has a resistivity in excess of a million ohm-meters.

Typical metals have less than one millionth of an ohm-meter.
For comparison, good insulators such as glass or rubber have resistivities of more than a billion ohm-meters.

If table salt is mixed with water, then it dissolves and sodium chloride ions go into solution and salt water has good conductivity. Seawater, for instance has about .2 ohm-meters resistivity which is a lot less than a metal but a lot more than dry table salt.

Table salt can also be heated to a temperature where it melts (801 centigrade). When any type of salt melts, it becomes a collection of molten charged atoms and conducts electricity well, though not as well as a metal.

Answer 2

Salts in solid form do not normally conduct electricity but salts in solution do.

A salt is an ionic solid.

Common table salt, NaCl, is a typical example. The chlorine atom pretty much completely takes the outer electron from the sodium atoms leaving to two atoms attracted primarily by electrostatic attraction. The solid form of salt is then the billions of charged atoms arranged in a crystalline array with alternating positive and negative charges. Because the electrons are strongly localized on the atoms, the do not readily move from one atom to the next in an electric field, i.e. when a voltage is applied. Table salt and most other salts exhibit virtually no conductivity and are thus insulators.

In water, things change. In water, the application of a voltage results in the movement of charge, but the charges are not nearly-free electrons as in metals, but rather ions (charged atoms or molecules). In pure water, the ions that are moving are the protons in the form of H3O+ and hydroxide ions, OH-. In other ionic solutions it is the dissolved ions themselves, for instance in salt water, sodium chloride dissociated into the ions Na+ and Cl-.

In some way, the conductivity of an ionic solution is easy to explain. When a voltage is applied, there develops an electric field. Any atom or molecule that has a net charge, q, feel a force, F=qE. Positive ions move in the direction of the field and negative ions move in the opposite direction. Both sets of moving charges add to make a current flows that in the direction of the field.

Pure water has few ions and is such a poor conductor that it is sometimes said that pure water does not conduct electricity. Even a low concentration of ionic impurities or salt changes this a great deal.

Answer 3

To make anything conductive either it should be in molten or in aqueous form.. dry salt is not conductive

Answer 4

Sodium chloride is an electrical conductor only in solution or when is melted.

Answer 5

Dry salt is not. But molten (melted) salt, and a solution

of salt in water, are both good conductors.

Answer 6

Only in an aqueous form