[问答题]
The bidentate ligand, phenanthroline (
3xj:ba. l 1dvaphen) has the structure below
lo:imjt4j,6.tj ;5i7yqiob z .
1.Use the diagram above to demonstrate how phenanthroline can act as a ligand to $M^+$ ions.
2.Phenanthroline forms the complex $[Cr(phen)_3]^{3+}$ with chromium ions.
(1)State the charge and the electron configuration of the central chromium ion.2
(2)Explain why the salts of $[Cr(phen)_3]^{3+}$ complex exhibit magnetic properties.1
3.The tetradentate (4-coordinate) ligand, salen, forms complexes with $Co^{3+}$ ions and can produce the compound [Co(salen)]Cl. Deduce the charge of the salen ligand.
