(i) Which is the last element in the series of the actinoids? Write the electronic configuration of this element. Comment on the possible oxidation state of this element.
(ii) What is lanthanoid contraction? Name an important alloy which contains some of the lanthanoid metals.

Explanation

Lawrencium (Lr, Z = 103) is the last element of actinoid series. (1) Electronic configuration `103^(Lr) = 86[Rn] 5 f^(14) 6d^(1) 7s^(2)`
Its possible oxidation state = + 3.