Ammonium Ion Concentration in 0.15M Solution of Ammonia
A compound of nitrogen/hydrogen, ammonia can exist as a weak base in solution in one of two forms: the un-dissociated form, NH3, or the dissociated, NH4+ form (ammonium and hydrooxide ions) (Papps, 2020). These concentrations depend on the degree to which ammonia is ionized. (Kb, equilibrium constant) The Kb value of ammonia is 1.80×10-5 (Gryaznov & Galaev, 2021). You can calculate the Kb values of ammonia in ammonia solutions of 0.15M using this equation.
[NH4+] = Kb*[NH3] = 1.80×10-5x 0.15 = 2.×10-6M
Therefore, in an ammonium solution of 0.15 M, there is 2.7×10-6 mg of ammonium.