Answer: NH4)2CO3
Explanation:
Ionic solids are the solids that are simply held together by ionic bonds. Ionic bonds are lattices that are typically made up of oppositely charged ions and they usually possess a high melting point.
An example of ionic bond is NH₄)₂CO₃ which is referred to as Ammonium carbonate. This is a salt and it readily degrades upon heating to carbon dioxide and gaseous ammonia.