Chemistry

Question Analysis
This question involves applying the period trend to a subset of Period 3 elements to identify the one with the highest first ionization energy.
The main focus is on using the left-to-right trend for specific p-block elements.

Key Concept Explanation
First ionization energy generally increases from left to right across a period. For the given Period 3 elements, their order from left to right is Al → Si → P. The rightmost element has the highest effective nuclear charge and smallest atomic radius, resulting in the highest ionization energy.

Step-by-Step Solution
1. Recall the Period 3 order of the given elements: Al (Group 13) → Si (Group 14) → P (Group 15).
2. Apply the period trend...