Ionic compounds dissolve in water if the energy given off when the ions interact with water molecules compensates for the energy needed to break the ionic bonds in the solid and the energy required to separate the water molecules so that the ions can be inserted into solution.

Are ionic compounds soluble or insoluble in water?

Most ionic compounds are soluble in water. Polar water molecules have a strong attraction for charged ions and the charged ions become solvated as they dissociate into the water and ionic compounds are soluble in water.

Are covalent compounds soluble in water?

Water is a polar solvent, but covalent compounds are nonpolar. This implies that covalent compounds don't dissolve in water and make a separate layer on the surface of the water. Hence we can say that covalent compounds are insoluble in water.