NEET Exam Model Paper 2

When an electron is removed from neutral helium atom,it becomes hydrogen like atom. Ionisation energy of hydrogen like atom is given by
Eion=+Z2Rhc
For He,Z=2,Rhc=13.6eV
Energy required to liberate second electron from helium is
E2=Eion=(2)213.6eV=54.4eVEnergy required to remove both the two electrons from helium nucleus is
E1+E2=24.6+54.4eV=79eV