The properties of transition metals

In a nutshell

Most metals are transition metals. Transition metals can be found between groups $2-3$ on the periodic table. Transition metals have particular physical properties as well as being able to possess multiple oxidation states.

Physical properties

Transition metals share common properties with metals such as:

Conducting heat
Ability to conduct electricity both in solid and liquid states
Being very lustrous (shiny when cut)

There are some differences between transition metals and other metals. Transition metals tend to have:

Higher melting points
Higher density
More than one oxidation state
Greater strength
Greater hardness

It is important to remember that these are typical properties, some transition elements may not show all of them. Gold for instance is not hard, it is in fact soft yet it is still a transition metal.

Metal	Position	Melting Point $(\degree C)$	Density $(g/cm^3)$	Hardness $(Mohs\ scale)$
$Na$	Group $1$	$98$	$0.97$	$0.5$
$Mg$	Group $2$	$650$	$1.74$	$2.5$
$Ti$	Transition	$1668$	$4.50$	$6.0$
$Cr$	Transition	$1907$	$7.19$	$8.5$
$Fe$	Transition	$1538$	$7.87$	$4.5$
$Zn$	Transition	$420$	$7.13$	$2.5$

Note: In the table the transition elements tend to have higher melting points, higher densities and are harder.

The position of the transition metals in the periodic table is shown below.

Chemistry; Separate chemistry 1; KS4 Year 10; The properties of transition metals

Transition elements as catalysts

Transition elements are often used as catalysts due to their ability to take up multiple oxidation states. Catalysts speed up the rate of reaction without being used up by the reaction.

Examples

Common transition metal catalysts include iron in the Haber process or platinum catalytic converters in cars.

Note: An oxidation number/state is a number given to each atom in a compound to represent the number of electrons they have. So, iron can have the oxidation number of $2+$ or $3+$

Transition metals and coloured compounds

When a group $1$ metal is dissolved in water they will typically form white compounds. However, transition elements form a variety of colours.

Compound	Copper $(II)$	Iron $(II)$	Iron $(III)$	Cobalt $(II)$	Vanadium $(V)$
Colour	Blue	Pale green	Orange / brown	Pink	Yellow / orange

Chemistry; Separate chemistry 1; KS4 Year 10; The properties of transition metals

Iron has the ability to be more than one colour. This is because iron has many different stable oxidation states, for each oxidation state there is a different colour.