Question

The positions of three elements A, B and C in the periodic table are indicated below:
(a) State whether element C would be a metal or a non-metal. Why?
(b) Which is the more active element, A or C? Why?
(c) Which type of ion (cation or anion) will be formed by the element C? Why?

Answer 1

Answer:

(a) Metallic character of elements decrease as we move horizontally left to right in the periodic table. The element A belongs to group 17 which is on the right side of the periodic table. Hence, element A does not show metallic character. It is a non-metal.

(b) The chemical reactivity decreases on going down in a group. Thus, element C is less reactive than element A.

(c) The atomic size decrease on going from left to right in a period. Hence, the atom of C will be smaller in size than an atom of B.

(d) Element A belongs to group 17 which has 7 valence electrons. It needs one electron to get noble gas configuration. So, it will accept 1 electron and form a negatively charged ion, A-. The negatively vahrged ion is called an anion. Thus, element A will form an anion.

Answer 2

Periodic Table

Explanation:

The image is missing in the question to show the options. Please find the attached picture for the image. The answer is with respect to the attached picture only.

(a) Element C is a non-metal. Metals tend to lose electrons. Element C belongs to Group 17 and has 7 valence electrons. So it has the tendency to gain one electron. Hence it is a non-metal.

(b) Electronegativity increases from left to right in a period due to the increase in effective nuclear charge and decreases from top to bottom in a group due to the increase in atomic size. Hence Element A is the most active element.

(c) Element C has 7 valence electrons and tends to gain one electron to form the octet. So it will form an anion.