Question

Explain the following: Electrovalent compounds dissolve in water whereas covalent compounds do not.

Answer 1

Hint: The process of dissolution of a compound in a particular solvent depends on the nature of intermolecular interactions present between the solute-solute and solvent-solvent particles. If the interactions between solute and solvent are of similar kind then the solvent dissolves easily.

Complete answer:
Chemistry deals with the principle of dissolves like when we talk about solubility of different types of compounds in water.
Electrovalent compounds are basically ionic compounds that are formed from the strong electrostatic interactions between the oppositely charged ions present in the ionic compound. Covalent molecules are made up of neutral atoms.
Water is a covalent molecule but has a high dielectric constant due to which it is known as a polar solvent. It only dissolves compounds that are similar in nature to that of water and should therefore have high polarity.
Ionic compounds dissociate completely in the presence of water and each ion gets extensively hydrated and surrounded by water molecules that stabilize these ions in their non-bonded state. The non-polar or less polar covalent molecules do not break apart on hydration and their neutral atoms do not interact efficiently with water.
Therefore the strong polar interactions between electrovalent compounds and water is responsible for their better solubility as compared to covalent compounds.

Note:
Ions are formed by the process of a complete exchange of electrons between electropositive metals and electronegative non-metallic elements, whereas covalent molecules are formed through sharing of electrons and have a little polarity.