Question

(i) Why is the second ionisation enthalpy of Ca is more than its first ionisation enthalpy​

Answer 1

ca^+2 has pseudo inert gas configuration which makes it behave like a noble gas. as IE means the amount of energy required to remove the most loosely bound electron of an atom is known a s ionisation enthalpy

thus ca shows more stability at its 2nd IE

Answer 2

Electron is more tightly bound by the nucleus in an cation as the number of proton remains the same as in neutral atom whereas number of electron is one less than the proton.This increases the attraction between the valence sheel electrons and the nucleus So, second ionization enthalpy is always higher than the first ionisation enthalpy for every element.

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