• # question_answer Which of the following ions form most stable complex compound [MP PMT 1995] A) $C{{u}^{++}}$ B) $N{{i}^{++}}$ C) $F{{e}^{++}}$ D) $M{{n}^{++}}$

The magnitude of stability constants for some divalent metal ions of the first transition series with oxygen or nitrogen donar ligands increases in the order. $M{{n}^{2+}}<F{{e}^{2+}}<C{{o}^{2+}}<N{{i}^{2+}}<C{{u}^{2+}}<Z{{n}^{2+}}$