For which element the second ionization enthalpy is expected to be greater, N or O ?

Name the element with highest ionization enthalpy.

Why the second ionization enthalpy is greater than the first ionization enthalpy?

How would you explain the fact that the first ionization enthalpy of Lithium is lesser than that of Beryllium but its second ionization enthalpy is greater than that of Beryllium?

How would you explain the fact that the first ionization enthalpy of Lithium is lesser than that of Beryllium but its second ionization enthalpy is greater than that of Beryllium?

The second ionization enthalpy of alkali metals is ______

The first ionization enthalpy of O is lower than that of N.

Among the second period elements the actual ionization enthalpies are in the order Li Explain why O has lower Delta_iH than N and F ?