Question

A, B, C are three elements with atomic numbers, Z-1, Z, and Z+1, respectively. B is an inert gas. Identify the group to which A and C belong.

• A. Alkali metal, Alkaline earth metal
• B. Halogen, alkali metal
• C. Inert gas, alkalimetals
• D. Halogens, Inert gas

Answer 1

The correct option is B Halogen, alkali metal

A, B, C are 3 elements with atomic number Z-1, Z, Z+1, respectively. As the atomic number of A is one less than B.

Since B is an inert gas.
$\therefore$ A is a $halogen$.

As the atomic number of C is greater than B, so C is an $alkalimetal$.