What is long form of the periodic table? Discuss in brief its salient structural features.
What are the advantages of classifying the elements into s, p, d and f-block elements?
These are:
(i) By classifying the elements into s, p, d and f blocks, we can study their physical and chemical properties in a very organised and systematic manner.
(ii) By knowing the block of the element, it is very easy to study the general behaviour and important properties of the elements. For example if the element belongs to s-block, it means it must have 1 or 2 electrons in outermost shell. Hence it must have low value of IE, strongly metallic and electropositive character and form cations easily.
(iii) This classification of elements also explains why properties of d-block elements vary slightly within the same period. This is because inner (n -1) d orbital is being progressively filled up.
(iv) In f-block elements there is progressively filling of (n - 2) f orbitals and this classification also explains why f-block elements are nearly identical in their chemical properties.
Which element do you think would have been named by:
(i) Lawrence Berkeley Laboratory
(ii) Seaborg's group?