The position of three elements A, B and C in the periodic table is show below:

CBSE Class 10 CBSE Class 10 Science
,
1

The position of three elements A, B and C in the periodic table is show below:

image
image.png758×167 45.1 KB

Give reasons to explain the following:
1.Element A is metal.
2 Element C has a larger size than element B.
3.Element B has a valency of

2

  1. Element A is a metal, because it belongs to group. So, it loses its one valence electron easily to form a monovalent positive ion.

  2. Element C has a larger size than element B because on moving from left to right in a period, the atomic number of elements increases of i.e., the extra electrons are being added to the same shell. Moreover, atomic size increases on moving down in a group.

  3. Element B has a valency of 3 because it loses 3 valence electrons to achieve the nearest inert gas configuration, so the valency is 3.