Q. The increasing order of first ionisation enthalpies of the elements B, P, S and F (lowest first) is
A) $F < S < P < B$
B) $P < S < B < F$
C) $B < P < S < F$
D) $B < S < P < F$
Explanation
(d)
Examine the positions in Periodic Table.
B C N O F
P S
Phosphorus is having stable half-filled configuration.
Hence, order is $B < S < P < F$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.