Question

Element X has the second highest electronegativity in the modern periodic table. To which group and period does this element belong to?

• A. ${16}^{th}$ group and $2^{nd}$ period
• B. ${14}^{th}$ group and $3^{rd}$ period
• C. ${17}^{th}$ group and $2^{nd}$ period
• D. ${11}^{th}$ group and $3^{rd}$ period

Answer 1

The correct option is A ${16}^{th}$ group and $2^{nd}$ period

Electronegativity is the tendency of an atom to gain electron(s) in order to attain noble gas configuration. Since it decreases down the group and increases across a period from left to right, fluorine has the highest electronegativity in the periodic table.

Comparing the electronegativity of oxygen and chlorine, we see that electronegativity of oxygen is higher than that of chlorine. This is because chlorine has an extra shell (energy level) and the nuclear force of attraction is low compared to that of oxygen.

Thus, element X is oxygen and has the second highest electronegativity. It belongs to the ${16}^{th}$ group and $2^{nd}$ period of the periodic table.