Question

Which of the following statements best explains why the atomic radius increases from top to bottom of the periodic table? A. The electronegativity decreases from top to bottom of the periodic table, so the atoms near the bottom have an increased capacity for electrons. B. For the atoms lower in the periodic table, there is more difference in charge between the electrons and the protons, which allows electrons to orbit farther from nucleus. C. The ionization energy decreases from top to bottom of the periodic table, so the atoms near the bottom have an increased capacity for electrons. D. For the atoms lower in the periodic table, the valence electrons are in higher energy levels and farther from the nucleus.

Answer 1

Answer:

D. For the atoms lower in the periodic table, the valence electrons are in higher energy levels and farther from the nucleus.

Explanation:

Atomic radius increases down the group because down the group, there an increase in the number of principle energy levels occupied. Now, these higher principal energy levels are made up of orbitals that are larger than the orbitals from the lower energy levels in size.

Therefore, the effect of this is that the greater number of principal energy levels will outweigh the increase in nuclear charge since nuclear charge also increases down the group and this in turn makes the atomic radius to increase as we go down the group.

Answer 2

Answer: C. For the atoms lower in the periodic table, the balance electrons are in higher energy levels and farther from the nucleus.

Explanation: As the valance electrons orbit farther from the nucleus the energy level increases from the top to the bottom of the periodic table. So the atoms lower in the periodic table, the balance electrons are in higher energy levels and farther from the nucleus, which result in an increase in the atomic radius.