Question

part b: multiple choice

1. which element has the largest atomic radius?

a) li b) na c) k d) rb

1. which element has the smallest atomic radius?

a) o b) f c) n d) c

1. as you move down group 1 (the alkali metals), atomic radius:

a) increases b) decreases c) stays the same d) cannot be predicted

1. which of the following explains why atomic radius decreases across a period?

a) more shielding electrons are added
b) electrons are lost

Explanation:

Step1: Recall atomic - radius trends

Atomic radius increases down a group and decreases across a period.

Step2: Answer question 6

Li, Na, K, and Rb are in Group 1. As we move down the group, atomic radius increases. Rb is the lowest in the group among them, so it has the largest atomic radius.

Step3: Answer question 7

C, N, O, and F are in the same period (Period 2). Atomic radius decreases across a period. F is the right - most among them, so it has the smallest atomic radius.

Step4: Answer question 8

For elements in Group 1 (alkali metals), as we move down the group, new electron shells are added, and the atomic radius increases.

Step5: Answer question 9

Across a period, the number of protons increases, and the electrons are added to the same shell. The increased nuclear charge pulls the electrons closer, resulting in a decrease in atomic radius.

Answer:

1. d) Rb
2. b) F
3. a) Increases
4. None of the given options are correct. The correct reason is that the nuclear charge increases while electrons are added to the same shell.