Question

Can molecular hydrogen (H2) form hydrogen bonds with other molecules (CH4, CO2, N2)? According to IUPAC's definition, the hydrogen bond is an attractive interaction between a hydrogen atom from a molecule or a molecular fragment X–H and an atom or a group of atoms in the same or a different molecule. What is the correct conclusion?

a) Yes, with all mentioned molecules
b) No, only with CH4
c) Yes, but only with N2
d) No, hydrogen bonding is not possible with any of them

Answer 1

Hydrogen bonding is only possible when a hydrogen atom is covalently attached to highly electronegative atoms such as fluorine, oxygen, or nitrogen. Since H2, CH4, CO2, and N2 lack this condition, they cannot form hydrogen bonds with each other; thus, molecular hydrogen (H2) cannot form hydrogen bonds with the mentioned molecules. The correct option is D.

Step-by-step explanation:

Hydrogen bonding is a specific type of intermolecular attractive force that occurs when a hydrogen atom, which is covalently bonded to a highly electronegative atom like fluorine, oxygen, or nitrogen (the FON trio), is attracted to a lone pair of electrons on an atom in a neighboring molecule.

Since molecular hydrogen (H2) does not contain hydrogen bonded to any of these electronegative elements, it cannot engage in hydrogen bonding with other molecules like CH4, CO2, or N2. All these mentioned molecules lack the highly electronegative atoms with lone pairs that are necessary for forming hydrogen bonds.

Therefore, the correct conclusion is that hydrogen bonding is not possible with any of the mentioned molecules, corresponding to option (d).