Question

question 47 (1 point)
which of the following statements correctly compares the relative size of an ion to its neutral atom?
o a the radius of a cation is identical to the radius of its neutral atom.
o b the radius of an anion is identical to the radius of its neutral atom.
o c the radius of an anion is greater than the radius of its neutral atom.
o d the radius of a cation is greater than the radius of its neutral atom.

question 48 (1 point)
which of the following factors contributes to the increase in ionization energy from left to right across a period?
o a an increase in the size of the nucleus
o b fewer electrons in the highest occupied energy level
o c an increase in the number of protons
o d an increase in the shielding effect

question 49 (1 point)
as you move from left to right across the second period of the periodic table
o a atomic mass decreases.
o b atomic radii increase.
o c ionization energy increases.
o d electronegativity decreases.

Explanation:

• Question 47:
• Cations are formed by losing electrons. When an atom loses electrons, the remaining electrons are more strongly attracted to the nucleus, so the radius of a cation is smaller than that of its neutral atom.
• Anions are formed by gaining electrons. The additional electrons increase electron - electron repulsion, and the electron cloud expands. So the radius of an anion is greater than that of its neutral atom.
• Question 48:
• Ionization energy is the energy required to remove an electron from an atom. As we move from left to right across a period, the number of protons in the nucleus increases. This increases the nuclear charge, which more strongly attracts the electrons. So, it becomes more difficult to remove an electron (higher ionization energy).
• The size of the nucleus (in terms of volume) is not the main factor affecting ionization energy in this context. The number of electrons in the highest - occupied energy level does not decrease from left to right across a period (it increases). The shielding effect (due to inner - shell electrons) remains relatively constant across a period (since the number of inner - shell electrons does not change).
• Question 49:
• As we move from left to right across the second period of the periodic table:
• Atomic mass generally increases (because the number of protons and neutrons increases).
• Atomic radii decrease (due to the increasing nuclear charge attracting the electrons more strongly).
• Ionization energy increases (as explained in Question 48, due to the increasing nuclear charge).
• Electronegativity increases (because atoms have a greater tendency to attract electrons as the nuclear charge increases).

Answer:

• Question 47: C. The radius of an anion is greater than the radius of its neutral atom.
• Question 48: C. an increase in the number of protons
• Question 49: C. ionization energy increases.