Question

Which of the following does not have a hydrogen bond?
a.) Phenol
b.) Liquid ammonia
c.) Water
d.) HCl

Answer 1

Hint: Elements having a very high electronegativity possess the ability to form hydrogen bonds. In order to solve this question, look at the compounds given in the question and check if it is made of a highly electronegative element.

Complete step by step solution:
Hydrogen bond is defined as the attractive force which binds the hydrogen atom of a molecule with the electronegative atom of another molecule.
Electronegativity of an element is defined as the ability of an atom in a chemical compound to attract a shared pair of electrons towards itself. Only three elements of the modern periodic table form hydrogen bonds – Oxygen, Nitrogen and Fluorine.

The electronegativity of H-bonds forming compounds is –
Fluorine – 3.98
Oxygen – 3.44
Nitrogen – 3.04

Let us look at the options given above –
Phenol – contains Oxygen, hence shows H-bonding.
Liquid ammonia – contains Nitrogen, hence shows H-bonding.
Water – contains Oxygen, hence shows H-bonding.
Hydrochloric acid – does not contain Oxygen, Nitrogen or Fluorine, does not show hydrogen bonding.
Therefore, the answer is – option (d) – Hydrochloric acid.

Additional information: Chlorine has a high electronegativity, but it does not show H-bonding since it has a greater size.

Note: Hydrogen bonds are of two types –
Intermolecular Hydrogen bond
It is formed between two different molecules of the same or different compounds.
For example – H-bond in case of water molecules.
Intermolecular Hydrogen bond
It is formed when a hydrogen atom is in between the two highly electronegative atoms present within the same molecule.
For example – H-bond between two oxygen atoms in o-nitrophenol.