Transition Metals
- The transition metals are located between Groups 2 and 3 in the centre of the periodic table
- They are very lustrous, they are hard, strong and are good conductors of heat and electricity
- They are highly dense metals and have very high melting points
- Transition metals can have more than one oxidation state as they can lose a different number of electrons, depending on the chemical environment they are in
The transition elements on the Periodic table
The melting point, density and common ions of the elements Cr, Mn, Fe, Co, Ni and Cu are shown below
Transition Metals Table
- Compounds containing transition metals in different oxidation states will have different properties and colours in aqueous solutions
The colours produced by ions of the transition elements
Examiner Tip
Note that transition metals themselves do not display a range of colours, it is the compounds they form that are colourful.
- The transition metals are used extensively as catalysts which are substances that speed up the rate of a reaction without being used up in the process
- They do not take part in the reaction
- Their catalytic characteristics stem from their ability to interchange between a range of oxidation states
- This allows them to form complexes with reagents which can easily donate and accept electrons from other chemical species within a reaction system
- Common transition metal catalysts include:
- Iron which is used in the Haber Process
- Vanadium pentoxide (V2O5) which is used in the Contact Process to produce sulfuric acid
- Nickel which is used in the hydrogenation of alkenes
Examiner Tip
Although scandium and zinc are in the transition metal area of the Periodic Table, they are not considered transition elements as they do not form coloured compounds and have only one oxidation state.