Ionisation entalpy of Li is 520kJ/mol while that of F is 1681kJ/mol.Explain.
Dear Student,
Lithium and fluorine are present in 2nd period. As we know, that the size of atom decrease on going along the period. Size of fluorine is smaller than lithium. Fluorine is most electronegative element in the periodic table. So it is not easy to knock out an electron from the fluorine atom while it is easy to knock out electron from lithium as it is electropositive element.
Lithium easily release electron to acquire noble gas electronic configuration, while fluorine gains an electron to acquire noble gas electronic configuration. That's why the ionisation energy of Li is less than that of F.
Regards
Lithium and fluorine are present in 2nd period. As we know, that the size of atom decrease on going along the period. Size of fluorine is smaller than lithium. Fluorine is most electronegative element in the periodic table. So it is not easy to knock out an electron from the fluorine atom while it is easy to knock out electron from lithium as it is electropositive element.
Lithium easily release electron to acquire noble gas electronic configuration, while fluorine gains an electron to acquire noble gas electronic configuration. That's why the ionisation energy of Li is less than that of F.
Regards