Looking at the nickel complexes as an example, it is found that those formed with ammoniagive the complex [Ni(NH3)6]2 and when formed with ethylenediamine the complex [Ni(en)3]2 is the result. Even though both are octahedral complexes, why do you think that nickel iscoordinated with six ammonia ligands in one case and only three ethylenediamine ligands inthe other