Sodium chloride (table salt) consists of Na+ and Cl- . Each has a charge of one. In calcium carbonate (chalk) each ion has a charge of two (Ca2+ and CO32-). Salt does dissolve in water but chalk does not dissolve. How do you think the charge of the ions influences whether an ionic compound will dissolve?

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.

the maximum mass of nh3 is nh3 in grams