The electronic configuration of the element T is 2, 8, 8, 1.

(i) What is the group number of T ?

(ii) What is the period number of T ?

(iii) How many valence electrons are there in an atom of T ?

(iv) What is the valency of T ?

(v) Is it a metal or a non-metal ?

Match the atomic number 19, 15, 8, 4, and 2 with each of the following :

(i) A metal of valency one.

(ii) A solid non-metal of period 3.

(iii) A rare gas.

(iv) A gaseous element with valency 2.

(v) An element of group 2.

Give the trends in atomic size on moving :

(i) Down the group,

(ii) Across the period left to right.

Arrange the elements of second and third period in increasing order of their atomic size (excluding noble gases).