The position of eight elements in the Modern Periodic Table is given below where atomic numbers of elements are given in the parenthesis.

(i) Write the electronic configuration of Ca. (ii) Predict the number of valence electrons in Rb. i (iii) What is the number of shells in Sr? (iv) Predict whether K is a metal or a non-metal. (v) Which one of these elements has the largest atom in size? (vi) Arrange Be, Ca, Mg and Rb in the increasing order of the size of their respective atoms.

Explanation

(i) Electronic configuration of Ca - 2, 8, 8, 2
(ii) Valence electrons in Rb is 1.
(iii) Five
(iv) Metal
(v) Rb is biggest in size.
(vi) Be < Mg < Ca < Rb