The atomic radius of germanium (Z = 32) is smaller than the atomic radius of potassium (Z = 19) because of ________
A) a change in the n quantum number.
B) an increase in the effective nuclear charge.
C) the fact that p and d orbitals have the same orbital penetration.
D) a decrease in the effective nuclear charge.
E) germanium having 32 rather than 19 electrons.

Question

Quizplus · Accepted Answer

The atomic radius is affected by the effective nuclear charge, which is the positive charge felt by the valence electrons from the nucleus. As the number of protons in the nucleus increases, the effective nuclear charge increases, leading to a stronger attraction between the nucleus and the electrons, causing the atomic radius to decrease. In this case, germanium has more protons than potassium, leading to a higher effective nuclear charge and a smaller atomic radius.

The Atomic Radius of Germanium (Z = 32) Is Smaller