The energy is required to remove e− from singly ionized helium atom=54.4eV. The energy required to remove e− from a helium atom =xeV, given 54.4eV=2.2x⇒x=24.73eV. The energy required to ionize helium atom =79.13eV≈79eV.
JEE Main 2018 — Physics Modern Physics
The energy required to remove the electron from a singly ionized Helium atom is 2.2 times the energy required to remove an electron from helium atom. The total energy required to ionize the Helium atom completely is close to
Held on 15 Apr 2018 · Verified 6 Jul 2026.
34eV
20eV
79eV
109eV
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