Write short notes on the following types of elements –

transition and inner transition elements

Transition and inner transition elements —

Transition elements —

1. The elements of group 3 to 12 [IB to VIIB & VIII] are called Transition elements.
2. They are all metals.
3. They lie at the centre of the periodic table between metals [highly electropositive] on the left and non-metals [highly electronegative] on the right.

Inner transition elements —

1. Lathanide [Rare earths] and Actinides series are called inner transition elements.
2. They lie at the bottom of the periodic table in two horizontal rows [14 elements each].
3. Lanthanide series : from Cerium ⁵⁸Ce to Lutetium ⁷¹Lu : [Period - 6]
4. Actinide series : from Thorium ⁹⁰Th to Lawrencium ¹⁰³Lr: [Period - 7]
5. They are all metals and chemically very reactive [actinides are radioactive elements].