transition metals Flashcards
what is a transition metal
element that forms at least one stable ion with a partially filled d subshell
key features of transition metals
3CV
-COMPLEX IONS
-COLOURED IONS
-CATALYTIC PROPERTIES
-VARIABLE OXIDATION STATES
co ordinate bond
shared pair of electrons which come from the same atom
ligand
an ion with a lone pair of electrons which can form a co-ordinate bond with a transition metal ion
coordination number
number of coordinate bonds
complex ion
central atom or ion surrounded by ligands
monodentate
each ligand forms 1 coordinate bond
bidentate
each ligand forms 2 coordinate bonds
multidentate
each ligand forms more than 2 coordinate bonds
octahedral transition metal complex
[Cu(H2O)6]2+
tetrahedral transition metal complex
[CoCl4]2-
square planar transition metal complex
[Ni(CN)4]2-
liners transition metal complex
[Ag(NH3)2]+
chelate effect
-occurs when a monodentate ligand is substituted by a bidentate/multidentate ligand
-large increase in entropy which is thermodynamically favourable
explain why this reaction is feasible
-^S is positive
-more moles of products so more disorder
-breaking 6 bonds and forming 6 bonds
-^H is approximately zero
-so ^G is less than zero so the reaction is feasible