Question
Question: Arrange \(N{H_3}\), \({H_2}O\) and HF in order of increasing magnitude of hydrogen bonding and expla...
Arrange NH3, H2O and HF in order of increasing magnitude of hydrogen bonding and explain the basis for your arrangement.
Solution
Hydrogen bonding is defined as the attractive force between hydrogen atoms of one molecule with the most electronegative atom such as fluorine, oxygen, and nitrogen of another molecule.
Complete step by step answer:
As we know the magnitude of the hydrogen bonding depends upon the electronegativity of the atom which is linked to a hydrogen atom and also the size of the electronegative atom and electronegativity is directly proportional to the magnitude of hydrogen bonding i.e. we can say more will be the electronegativity, more will be the magnitude of hydrogen bonding, and if talk about the second factor i.e. size, it is inversely proportional to the magnitude of hydrogen bonding. Hence smaller the size more will be the magnitude of hydrogen bonding.
In the above case, the electronegativity of fluorine, oxygen, and nitrogen are in decreasing orders is given as:
Fluorine > Oxygen > Nitrogen.
And if we talk about the size of fluorine, oxygen, and nitrogen. The size of fluorine is smaller as compared to the size of oxygen which is smaller in size as compared to the size of nitrogen.
Hence from the above two factors, we can arrange the ammonia, water, and hydrogen fluoride in decreasing order of magnitude of hydrogen bonding as:
HF>H2O>NH3.
Note:
Hydrogen bonding is of two types:
Intermolecular hydrogen bonding: This type of hydrogen bonding is formed between two different molecules of the same or different type of compounds. The example of the molecule containing intermolecular hydrogen bonding is alcohol, water, etc.
Intramolecular hydrogen bonding: This type of hydrogen bonding is formed between the hydrogen atom and electronegative atom of the same molecule. For example in o-nitrophenol intramolecular hydrogen bonding is present.