Is ammonium ion a radical?

1 Answer
Mar 16, 2017

Answer:

#"Ammonium ion"# is not a radical species............

Explanation:

The ammonia molecule, #:NH_3# is conceived to have a lone pair of electrons localized on the nitrogen centre.

In aqueous solution, this lone pair is conceived to donate to an hydrogen ion in an acid base reaction as shown:

#NH_3(aq) + H_2O(l) rightleftharpoons NH_4^(+) + HO^-#

All chemical reactions conserve charge. Has charge been conserved here?

Certainly, we can measure the extent of this equilibrium reaction (conveniently by measuring the #pH# of the solution:)

#K_"eq"=([NH_4^+][HO^-])/([NH_3])=10^(-4.75)=1.78xx10^-5#.

In ammonium cation, there are SIX electrons associated with nitrogen, rather than the 7 required for neutrality. The nitrogen in ammonia is (so-called) quaternized, and thus bears a positive charge. Certainly, we can use ammonium salts such as #NH_4Cl#, and #(NH_4)_2SO_4# in the lab.

#"Ammonium nitrate"#, when mixed with fuel oil, is a potent high explosive.