What will be the atomic number of an element X which is placed in period 2 and group 17?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 9.
The element with an atomic number of 9, situated in period 2 and group 17 of the periodic table, is fluorine (F).
Fluorine is a very reactive nonmetal and is the first element in Group 17, commonly referred to as the halogens.