Q. Correct order of first ionization potential among the following elements is

 2093  220 J & K CETJ & K CET 2003 Report Error

Solution:

The ionisation potential increases from left to right in a period but -the first ionisation potential of nitrogen is greater than oxygen due to half-filled stable configuration and ionisation potential of is greater than due to completely filled s-orbital. Hence, the order of ionisation potential is as:
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