Knowing the formation constant of a metal M2+ with ligand EDTA is Kimx = 6.3 x 1021, calculate the equilibrium concentration of free M2+, [M2+), in a solution of 0.0125M of MY2- at pH 3.0 and pH 8.0, in presence of 0.005M NH3. The four formation constants of M2+ with ammonia are 6.1 x 102, 2.9 x 102, 1.15 x 102 and 99 respectively. From the difference in concentrations of free M2+ under different pH values, discuss the possible environmental implications. (Read Section 6.4.B and Ex.6.4 & Ex 6.5.)