Chemistry

Question Analysis
This question assesses the ability to compare and arrange elements based on their atomic radii, considering both group and period trends.

Key Concept Explanation
Atomic radius generally decreases from left to right across a period and increases down a group. By comparing the positions of the elements in the periodic table, we can determine their relative atomic radii.

Step-by-step Solution
1. Identify the elements: K (Group 1, Period 4), Ca (Group 2, Period 4), Sc (Group 3, Period 4), Ti (Group 4, Period 4).
2. Compare the elements within the same period (Period 4): K < Ca &l...