Answer:
a. NH3+ HCl → NH4Cl
c. 2O3 → 3O2
Explanation:
A redox reaction is a reaction in which there is loss or gain of electrons. As a result of that , there is a change in the oxidation number of the species involved in the reaction.
If we look at the species shown in the answer, there isn't any change in oxidation number as we move from left to right hence they are not redox reactions.
Redox reactions lead to change in oxidation number of species from left to right.
