Question

use the periodic table to rank the grey elements from smallest to largest. * (0.5 points)

Explanation:

Step1: Recall atomic radius trend

Atomic radius decreases across a period (left - to - right) and increases down a group.

Step2: Analyze positions

• B is in period 2, group 13.
• Al is in period 3, group 13.
• Se is in period 4, group 16.
• Br is in period 4, group 17.
• I is in period 5, group 17.

Since B < Al (down the group, radius increases), and within period 4, Se > Br (left - to - right, radius decreases), and Br < I (down the group, radius increases).

Answer:

B < Al < Br < Se < I