Which of the following statements correctly describes electronegativity and its trends in the periodic table?

• A. Electronegativity decreases from left to right across a period and increases down a group.
• B. Electronegativity increases both across a period and down a group.
• C. Electronegativity remains constant across periods and groups.
• D. Electronegativity increases from left to right across a period and decreases down a group.

Answer: (D)

Verified step by step guidance

1. Understand that electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond.
2. Recall the general trend of electronegativity in the periodic table: it increases as you move from left to right across a period because atoms have more protons, increasing the nuclear charge and attracting electrons more strongly.
3. Recognize that electronegativity decreases as you move down a group because atoms have more electron shells, which increases the distance between the nucleus and the valence electrons, reducing the nucleus's pull on bonding electrons.
4. Compare the given statements with these trends to identify which one correctly describes the behavior of electronegativity across periods and down groups.
5. Conclude that the correct description is: electronegativity increases from left to right across a period and decreases down a group.