The position of three elements A, B and C in the Periodic Table are shown below : Giving reasons, explain the following : (a) Element A is a non-metal. (b) Atom of element Chas a larger size than atom of element A. (c) Element B has a valency of 1.

The position of three elements A, B and C in the Periodic Table are sh

1.	The position of three elements A, B and C in the Periodic Table are shown below : Giving reasons, explain the following : (a) Element A is a non-metal. (b) Atom of element Chas a larger size than atom of element A. (c) Element B has a valency of 1.
Answer» Solution :(a) Element A has 7 electrons in the valence shell. It has a tendency to gain one electron to achieve nearest inert gas configuration. Elements which have a tendency to gain electrons are nonmetals. Thus, element A is a non-metal. (b) Atom of element Chas got three filled SHELLS whereas an atom of A has got TWO shells. Therefore, atom of element C has a larger size than atom of element A. (c) Element B has one electron (being in GROUP 1) in OUTERMOST shell. To gain stability, it has a tendency to lose one electron. Thus, it has a valency of 1.