If 18 ml of methanol is used to make an aqueous solution that is 15% methanol by volume, how many ml of solution is produced?

120.0 mL.

Explanation:

We suppose that the initial W% of methanol is 100.0 %

∴ (W%V) before dilution = (W%V) after dilution.

W% before dilution = 100.0 %, V before dilution = 18.0 mL.

W% after dilution = 15.0 %, V after dilution = ??? mL.

∴ V after dilution = (W%V) before dilution/W% after dilution = (100.0 %)(18.0 mL)/(15.0%) = 120.0 mL.

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.