How to calculate ionization energy of an atom provided energy of the electron at ground state? [closed]








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It is given that in ground state the energy of electron in hydrogen atom is $-2.18\times10^{-18}\mathrm{J}$. I'm required to calculate the Ionization Energy in kJ/mol


**Question for reference:**



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> At ground state the eng of electron in hydrogen atom is $-2.18\times10^{-18}\mathrm{J}$. Calculate the I.E in KJ/mol
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I could not find it in my book and also tried googling. None of these worked.


It is not a homework question. It is from a question booklet which have high chance of being asked in the upcoming exams.




* **Ionisation energy** : It is the minimum amount of energy required to remove an electron from the neutral gaseous atom.


If the electron is bound to the nucleus then its total energy will be negative. To separate the electron from the nucleus we should supply energy until the total energy of electron just becomes zero. So by definition the minimum amount of energy required to remove an electron from ground state will be $2.18 \times 10^{-18}J $, which is nothing but the Ionisation energy.


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