Transition Metals Flashcards
Key features of transition elements
-form complex ions
-coloured ions
-catalytic properties
Variable oxidation states
Define a ligand
An Ion or molecule with a lone pair of electrons with a lone pair of electrons which form a coordinate bond with a transition metal Ion
Define a complex ion
Is a metal atom or Ion surrounded by ligands
define coordination number
the number of coordinate bonds a transition metal ion forms
define a bidentate ligand
molecule or compound that has 2 separate atoms that each donate 1 electron pair to the central positive ion in a complex
what is complex is found in tollen’s reagent
[Ag(NH3)]+
2 square planers transition metal complexes
[Ni(CN)4]2- and [Pt(NH3)2Cl2]
why can only 4 Cl- ligands fit around a metal ion
Cl- ligand is too big
describe the Chelate effect
occurs when a monodentate ligand is substituted by a bidentate or multidentate ligand
why is cis platin important
binds to the DNA in cancer cells and stop cell replication
how does cis platin bind to the DNA in cancer cells and stop cell replication
the 2 Cl- on Cisplatin are substituted for 2 N atoms on adjacent Guanine bases
when do optical isormers occur in a complex
when complexes form with at least 2 bidentate ligands
why are transition metal compounds coloured
because they have partially filled d subshells
define ground state
when In a pure transition metal atom all d orbitals are of equal energy
why are electrond excited from one orbital to another
in transition metals the presence other atoms causes the d orbital to have slighly different energies
White light provides energy for an electron to move from a lower energy d orbital to a higher energy d orbital
