An element X belongs to 3^rd period and group 2 of the periodic table State:

(a) number of Valence electrons

(b) Valency

(c) metal or non-metal

(d) name of the element

In each of the following pairs, choose the atom having the bigger size:

(a) Mg (At. No. 12) or Cl( At. No. 17)

(b) Na (At. N0. 11) or K (At. No. 19)

The atomic numbers of three elements A, B and C are given below:

(i) Which element belongs to group 18?

(ii) Which element belongs to group 15?

(iii) Which element belongs to group 13?

(iv) To which period/periods do these elements belongs?

The following diagram shows a part of the periodic table in which the elements are arranged according to their atomic numbers. (The letters given here are not the chemical symbols of the elements):

(i) Which element has a bigger atom, a or f?

(ii) Which element has a higher valency, k or o?

(iii) Which element is more metallic, i or k?

(iv) Which element is more non-metallic, d or g?

(v) Select a letter which represents a metal of valency 2.

(vi) Select a letter which represents a non-metal of valency 2.

An element X is in group 2 of the periodic table:

(a) What will be the formula of its chloride?

(b) What will be the formula of its oxide?