Question

The position of three elements A, B and C in the Periodic Table are shown below:

Group 16	Group 17
- - - B	- A - C

 

(i) State whether A is a metal or a non-metal.
(ii) State whether C is more reactive or less reactive than A.
(iii) Will C be larger or smaller in size than B?
(iv) Which type of ion—cation or anion will be formed by element A?

Answer 1

(i) Metals lie on the left-hand side of the Periodic table whereas non-metals are found on the right-hand side. The element A is in group 17. Group 17 is on the right side of the Periodic table. Thus, element A is a nonmetal
(called halogen).
(ii) The chemical reactivity of non-metals decreases on going down in a group. In group 17, the chemical reactivity decreases on going down in a group. So, element C is less reactive than A.
(iii) The atomic size decreases in moving from left to right along a period. So, atom C will be smaller in size than B.
(iv) The element A of group 17 has 7 valence electrons. So, it will gain one electron to form a negatively charged ion (A–). The negatively charged ion is called an anion. So, element A will form an anion.