Two properties of ionic compounds are

Here is a short list of main properties:

They form crystals. ...

They have higher enthalpies of fusion and vaporization than molecular compounds.

They are hard.

They are brittle.

They have high melting points and also high boiling points.

They conduct electricity but only when they are dissolved in water.

Explanation:

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.

your parents i think this could be it