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?

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

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 Y is in second period and group 16 of the periodic table:

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

(ii) What is the number of valence electrons in its atom?

(iii) What is its valency?

(iv) What is the name of the element?

(v) What will be the formula of the compound formed by Y with sodium?

An element X has mass number 40 and contains 21 neutrons in its atom. To which group of the periodic table does it belongs?