1. General information on molten salts

The variety of molten salts is extreme, since there are as many as there are salts and salt mixtures; the only condition for the existence of molten salt is that it does not decompose before melting, and that it does not sublime excessively.

Molten salts can be completely, partially or practically non-ionized. Molten zinc chloride, for example, is in the form of a macromolecule and is virtually non-ionized when pure. However, when potassium chloride KCl is added, partial ionization occurs, depending on the amount of potassium chloride added. Pure molten potassium chloride, on the other hand, is fully ionized.

The melting temperatures of salts, pure or in mixtures, vary from ambient to over 1,000°C, depending on their nature.

...