Answer:
The correct answer is When melted they DO NOT conduct an electric current.
Step-by-step explanation:
I looked for the same question to know which options it gives as answers and the one that did not correspond to a characteristic of ionic compounds is that when melted they DO NOT conduct an electric current.
To melt the solid, the ionic bonds must be broken, separating the ions with opposite charges from each other. This generates that they become good conductors when molten, since the ions are free to move through the liquid and thus can carry an electric current.
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