Question

Conversion of atmospheric nitrogen to one molecule of ammonia by nitrogenase enzyme complex requires

• A. 4 molecules of ATP
• B. 6 molecules of ATP
• C. 8 molecules of ATP
• D. 16 molecules of ATP

Answer 1

The correct option is C 8 molecules of ATP

$N_2+8e^{-}+8H^{+}+16\mathrm{ATP}\to$$2{\mathrm{NH}}_3+H_2+16\mathrm{ADP}+16P_i$ Formation of 2 molecules of ammonia requires 16 molecules of ATP. So, formation of 1 molecule of ammonia will require 8 molecules of ATP.