Question

The electronegativities of N, C, Si and P are in the order

• A. P < Si < C < N
• B. Si < P < N < C
• C. Si < P < C < N
• D. P < Si < N < C
• E. Difficult to predict

Hint:

Remember the "FON" rule: Fluorine, Oxygen, and Nitrogen are the three most electronegative elements.

Answer 1

The Correct Option is C

Concept: Electronegativity is the tendency of an atom to attract shared electrons.
• It increases across a period (C < N).
• It decreases down a group (N > P and C > Si).

Step 1: Compare elements within the same periods.
Period 2: C ($2.5$) < N ($3.0$) Period 3: Si ($1.8$) < P ($2.1$)

Step 2: Compare elements across periods.
Since electronegativity decreases down a group, the second-period elements (C, N) will generally be more electronegative than the third-period elements (Si, P).

Step 3: Final Ranking.
Combining these: Si ($1.8$) < P ($2.1$) < C ($2.5$) < N ($3.0$).