Final answer:
A low melting point is not a common property of ionic compounds; they are characterized by high melting points, being hard and brittle, and conducting electricity when molten but not as a solid.
Step-by-step explanation:
The property that is not common to ionic compounds is having a low melting point. Ionic compounds are known for their distinctive characteristics, which include being hard, brittle, and capable of conducting electricity as a liquid but not as a solid.
They typically have high melting points and high boiling points. When they are solid, the ionic compounds have ions that are held in place and cannot move, which means they do not conduct electricity. However, when these compounds are in a molten state (liquid), the ions can move freely, and this allows the compound to conduct electricity.