Question

The elements A, B, C, D and E have atomic numbers 9, 11, 17, 12 and 13 respectively. The pair of elements which belongs to the same group of the periodic table is
(a) A and B
(b) B and D
(c) A and C
(d) D and E

Answer 1

Answer:

A and C

Explanation:

Florine have atomic number 9 and chlorine have 11. they both belong to 7 A group