Pauling's electronegativity scale measures the ability of an atom to attract electrons towards itself in a chemical bond. The electronegativity values of elements increase across a period and decrease down a group. Let's examine the elements in each option: -
Option A: Na Cs K
- This order is incorrect because electronegativity decreases as we move down a group. Therefore, Cs should have the lowest electronegativity, followed by K, and Na having the highest among them. -
Option B: Mg Al Si
- This is incorrect as well. Electronegativity increases as we move from left to right across a period, so Si should have a higher electronegativity than Al and Mg. -
Option C: B C Al
- This is partially correct but not the best match. Carbon has a higher electronegativity than both B and Al, but we need to check other options for a more precise match. -
Option D: N S P
- This is correct. Nitrogen (N) has the highest electronegativity among these three, followed by Sulfur (S) and Phosphorus (P), as electronegativity decreases as we move down a group. Thus, the correct order of electronegativity values is S P}\) .