Calculate the energy required for the process
He+(g)→He2+(g)+e−
The ionization energy for the H atom in the ground state is 2.18 ×10–18Jatom–1
Energy associated with hydrogen-like species is given by,
En=−2.18×10−18(Z2n2)J
For ground state of hydrogen atom,
△E=E∞−E1 =0−[−2.18×10−18{(1)2(1)2}]J△E=2.18×10−18J
For the given process,
He+(g)→He2+(g)+e−
An electron is removed from n = 1 to n = ∞.
△E=E∞−E1=0−[−2.18×10−18{(2)2(1)2}]J△E=8.72×10−18J
∴ The energy required for the process is 8.72×10−18J.