What minimum temperature is needed to dissolve 60 grams of NH4Cl in 100 g H2O?

At 70∘C , ammonium chloride has a solubility of about 62 g / 100 g H2O . This tells you that can only hope to dissolve 62 g of ammonium chloride for every 100 g of water before the solution becomes saturated.

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.