Question

Place the following compounds in order of increasing strength of intermolecular forces. HF H2 CH3Cl

Answer 1

Answer:

H2 < CH3Cl < HF

Explanation:

The intermolecular forces are the forces that bond the molecules together in a substance. There are three types of these forces:

1. Dipole induced -dipole induced, or London dispersion -> Is the weakest and is presented in nonpolar molecules, in which a dipole is induced and so the molecules are joined together;
2. Dipole-dipole -> Is stronger than the London dispersion and occurs in a polar molecule. In this case, the dipole already exists (partial positive and negative charges), so the poles are attracted;
3. Hydrogen bond -> It's the strongest and is formed when the hydrogen is bonded with a higher electronegativity element (F, O, and N).

So, the molecule of H2 is linear and formed by the same element, so, is nonpolar, and has London dispersion forces. The molecule of CH3Cl has 3 nonpolar bonds (C-H), and one polar bond (C-Cl), so it's polar and has dipole-dipole forces. And the HF molecule has hydrogen bonds.

*A polar bond is a bond formed by elements with different electronegativities.