Kindly provide detailed reactions involved in heterotrophic nitrification and aerobic denitrification and how to calculate the gibbs energy of these process
This software will calculate the GFE for you. It comes with a gas and aqueous database. http://dudleybenton.altervista.org/software/CREST614.zip The software is described in this book https://www.amazon.com/dp/B07SLBZJK3, which is free tomorrow (1/4/2020).