Question

Strongest hydrogen bond is present in:
A. ${H_2}O$
B. $N{H_3}$
C. ${H_2}S$
D. ${C_2}{H_5}OH$

Answer 1

To solve this question, we must first understand how wine is made. Then we need to assess the compounds that are used in the formation of wine and then only we can conclude the correct answer.

Complete answer:
Before we move forward with the solution of this given question, let us first understand some basic concepts:
Hydrogen Bonding : It refers to the formation of Hydrogen bonds, which are a special class of attractive intermolecular forces that arise due to the dipole-dipole interaction between a hydrogen atom that is bonded to a highly electronegative atom and another highly electronegative atom while lies in the vicinity of the hydrogen atom.
For example, in water molecules ${H_2}O$, hydrogen is covalently bonded to the more electronegative oxygen atom. Therefore, hydrogen bonding arises in water molecules due to the dipole-dipole interactions between the hydrogen atom of one water molecule and the oxygen atom of another ${H_2}O$molecule.
Step 1: ${H_2}O$: Since Oxygen is the only element after Fluorine, having the strongest H-bonding. So, if there is no H-bond Fluorine in the given options, we can say that this is our required answer.
Step 2: $N{H_3}$: Strength of H-bonding with Nitrogen is slightly weaker as compared to Oxygen. So this is not our answer.
Step 3: ${H_2}S$: No Hydrogen bonding is present.
Step 4: ${C_2}{H_5}OH$: Here also the molecule has Oxygen which is forming H-bond, but the ethyl group will make the H-bond weaker due to its Inductive effect.
And finally we can say that, Strongest hydrogen bond is present in ${H_2}O$.
So, clearly we can conclude that the correct answer is, ‘A. ${H_2}O$’ .

Note: The hydrogen bond is a weak bond. The strength of hydrogen bond is in-between the weak van der Waals forces and the strong covalent bonds.