Transition metals are a group of metals located in the centre of the periodic table, between groups 2 and 3 (or 2 and 13, depending on the table).
As you can see, most of the known metals are transition metals.
Transition metals have typical properties of metals:
Despite these similarities, they have notable differences compared to group 1 metals:
It’s also worth noting that transition metals can form ions with different charges. The table below shows some examples of transition metals and their common ions.
|Chromium (Cr)||Cr²⁺, Cr³⁺, Cr⁶⁺|
|Manganese (Mn)||Mn²⁺, Mn³⁺, Mn⁴⁺, Mn⁶⁺, Mn⁷⁺|
|Iron (Fe)||Fe²⁺, Fe³⁺|
|Cobalt (Co)||Co²⁺, Co³⁺|
|Copper (Cu)||Cu⁺, Cu²⁺|
The table below compares the melting points and densities of the first three group 1 metals with the transition metals above.
|Lithium (Li)||Group 1||181 °C||0.53 g/cm³|
|Sodium (Na)||Group 1||98 °C||0.97 g/cm³|
|Potassium (K)||Group 1||64 °C||0.89 g/cm³|
|Chromium (Cr)||Transition metal||1890 °C||7.19 g/cm³|
|Manganese (Mn)||Transition metal||1240 °C||7.20 g/cm³|
|Iron (Fe)||Transition metal||1538 °C||7.87 g/cm³|
|Cobalt (Co)||Transition metal||1492 °C||8.90 g/cm³|
|Nickel (Ni)||Transition metal||1453 °C||8.90 g/cm³|
|Copper (Cu)||Transition metal||1083 °C||8.92 g/cm³|
As you can see in the table, the melting points and densities of the transition metals are higher compared to the group 1 metals.
Transition metals form compounds with different colours based on the charge of the metal ion.
The most important ones to remember are:
A catalyst is a substance that speeds up the rate of reaction without being used up in the process. Transition metals are often used as catalysts. For example: