topic 15- transition metals Flashcards
d block elements
less sharp differences
similarities across periods are greater
chromium and copper
fills d orbital before s
arrange so have the lowest energy
less repulsion
ion formation
when loose or gain an electron it is lost/gained from 4s first so it is written second rather than first
what are transition metals
-def
-characteristics
dblock element which forms one or more stable ions with incomplete d orbitals
-hard solids
-high melting and boiling
-catalst
-coloured ions and compounds
ligands
species bonded to the metal ion by co-ordiate bonds (dative)
donate a pair of electrons to metal ions
transition metals with ligins are complex ions that carry a charge
coordination number
number of cooridinate bonds from the ligands to the central metal ions
types of ligands
monodentate - single lone pair
bidentate - two lone pairs
-1,2-diaminoethane
multidentate - multpiple lone pairs
-EDTA (ethylenediaminetetraacetic acid)
chelates
transition metals held in claw - the bond
naming complex ions
number of ligins prefix
-mono di tetra
name the ligands ending in o for ions
- chloro hydroxo
amine for NH3 and aqua for H2O
name the central metal ion
neutral and positive - naomal name
negative - latinaised name + ate
add oxidation number for central metal
octahedral
coordination number of 6
tetrahedral
4
sqaure planar
4
cistrans isomerism
e.g cis-platin trans-platin
-cis can be used in cancer treatment but trans cannot
linear
2
equation linking energy and frequency of light
ΔE = h𝝂
where ΔE = change of energy
h = Planck’s constant
𝝂 = frequency
what makes colours of transition metals
d orbitals split due to ligands
electrons absorb light in the visible region of the spectrum
to promote electrons to higher energy levels
the unabsorbed light is the colour shown/reflected
stability of complexes
comparison of stabilities of two complexes where the number of ligands has changed
types of reaction of ligands
redox
acid base
ligand exchange
coordination number change