Question

From top to bottom in most groups of elements, atomic radii tend to A. decrease because the nuclear charge increases. B. decrease because electrons are lost to other elements. C. increase because electrons are gained from other atoms. D. increase because additional energy levels are filled.

Answer 1

Answer: The correct answer is Option D.

Explanation:

Atomic radius is defined as the total distance from the nucleus to outermost orbital of the electron.

As moving from top to bottom, new shell is added around the nucleus. The outermost orbital gets far away from the nucleus and hence, the distance between the nucleus and outermost orbital gets increased.

Thus, the atomic radii of the elements increases as we move from top to bottom in a group.

Hence, the correct answer is Option D.

Answer 2

D. As more electrons are added to an element, the number of electron orbitals being filled increases