Q. The correct decreasing order of first ionisation enthalpies of five elements of the second period is
A) Be > B > C > N > F
B) N > F > C > B > Be
C) F > N > C > Be > B
D) N > F > B > C > Be
Explanation
(c)
In general ionisation energy increases as we move from left to right in a period. It is due to the increase in effective nuclear charge. $IE_{1}$of Be and N is high due to stable configuration. Hence, the order is as follows F > N > C > Be > B
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.