What intermolecular forces are present in #NH_3#?

2 Answers
Mar 25, 2018

Dispersion forces and hydrogen bonding....

Explanation:

And of course, the most significant intermolecular force is hydrogen bonding. The normal boiling point of ammonia is #-33.3# #""^@C#...this is extraordinarily elevated as compared with the boiling points of the other Group 15 hydrides...#PH_3, -87.7# #""^@C#, #AsH_3, -62.5# #""^@C#,...and this series is comparable with the hydrides of the Group 16 elements. For #H_2O# its normal boiling point is even more elevated as compared with the lower Group hydrides....

Again, as nitrogen, and oxygen, are the most electronegative elements of their Groups, the dipoles they form in their bonds with hydrogen are the MOST polar, and thus give rise to the greater intermolecular force, and therefore the greater boiling points...

I'm assuming you mean inter-molecular forces...

Explanation:

#NH_3# is polar and anionic in its aqueous form.

The following image illustrates the hydrogen-bonding intermolecular forces of attraction when #NH_3# is in its molecular form:

https://qph.fs.quoracdn.net/main-qimg-5e8b140491723544d35221f7d018e7c4

The next image illustrates the weak electromagnetic intermolecular forces of attraction when #NH_3# is in its aqueous form:

https://www.tutorvista.com/content/chemistry/chemistry-ii/acids-bases/alkali.php

I hope this helps!