Consider the reaction between 75.5 mL of 0.247 M barium hydroxide and 95.0 mL of 0.330 M HCl. Find the mole ratio of hydrochloric acid to barium hydroxide, compare to the theoretical one, and determine the limiting reactant.

Explanation:

Ba( OH)₂ + 2HCl = BaCl₂ + 2H₂O .

75.5 mL of 0.247 M barium hydroxide = .0755  x .247 = .01864 moles

95.0 mL of 0.330 M HCl = .095 x .33 = .03135 moles

mole ratio of  hydrochloric acid to barium hydroxide

= .03135 /  .01864 = 1.68

theoretical ratio = 2 /1 = 2

As the theoretical ratio is more , therefore HCl is the limiting reactant  .

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.