Question

1. what is the general trend for atomic radius as you move from right to left across a period on the periodic table?

• a. atomic radius increases
• b. atomic radius decreases
• c. atomic radius remains constant
• d. atomic radius increases then decreases

1. which factor is primarily responsible for the increase in atomic radius across a period?

• a. increasing number of electron shells
• b. decreasing nuclear charge with the same number of electron shells
• c. increasing nuclear charge with the same number of electron shells
• d. decreasing number of valence electrons

1. as you move up a group in the periodic table, what happens to the ionization energy?

• a. it increases
• b. it decreases
• c. it remains constant
• d. it increases then decreases

Explanation:

• Question 1: As you move from right to left across a period, the number of protons (nuclear charge) decreases while the number of electron shells remains the same. So, the attraction between the nucleus and electrons weakens, and atomic radius increases.
• Question 2: When moving across a period, the number of electron shells is constant. A decrease in nuclear charge (fewer protons) means less attraction for electrons, leading to a larger atomic radius.
• Question 3: As you move up a group, the atomic radius decreases (fewer electron shells). Electrons are closer to the nucleus and more strongly attracted. So, it takes more energy to remove an electron (ionization energy increases).

Answer:

1. A. Atomic radius increases
2. B. Decreasing nuclear charge with the same number of electron shells
3. A. It increases