Question

question 7. rank the following elements in order of increasing atomic radius (from smallest to largest).
elements: phosphorus (p), sulfur (s), chlorine (cl), silicon (si)
answer:
options: phosphorus (p), sulfur (s), chlorine (cl), silicon (si)

Explanation:

Step1: Recall atomic radius trend

In a period (row) of the periodic table, atomic radius decreases from left to right. This is because as we move right, the number of protons increases, pulling the electrons closer to the nucleus, reducing the atomic radius.

Step2: Identify period and positions

Si, P, S, Cl are all in period 3. Their positions from left to right are: Si (group 14), P (group 15), S (group 16), Cl (group 17).

Step3: Apply the trend

Since atomic radius decreases left to right in a period, the order from smallest (rightmost) to largest (leftmost) is Cl < S < P < Si.

Answer:

Chlorine (Cl) < Sulfur (S) < Phosphorus (P) < Silicon (Si)