Answer:
Bacteria that metabolize NO2- to give rise to NH4+ belongs to the family of denitrifying bacteria and nitrate ammonification bacteria such as pseudomonas.
Step-by-step explanation:
Denitrifying bacteria uses NO2- as electron aceeptor thus converting the nitrite ion (NO2-) to ammonium ion(NH4+).
a) The above reaction is a reduction reaction because NO2- or nitrite ion accept electron to generated its reduced form known as ammonium(NH4+).
b) NO2- acting as electron acceptor in this reaction.