3.2 d-Block Elements

  Periodic Table

• The elements of the periodic table in which the last electron gets filled up in the d orbital are called d-block elements.
• The $d$-block elements are placed in groups named $ III B, IV B, V B, VI B, VII B, VIII B, I B \:and \:II B.$
• In $d$-block elements the electrons get filled up in the $d$ orbital of the penultimate shell. That is why these elements are known as transition elements.
• Through the total number of $d$-block elements are 33 in the periodic table but there are only 30 transition elements, because only these elements are transition in which d orbital is partially filled.
• The general formula of these elements is $\left( {n - 1} \right){s^2},{p^6},{d^{1 - 10}}n{s^{1 - 2}}$ where n=4 to 7.
• All of these elements are metals.
• Out of all the d-block elements mercury is the only liquid element.