NEET2010PhysicsAtomic PhysicsActual
The energy of a hydrogen atom in the ground state is -13.6 eV . The energy of a He ⁺ ion in the first excited state will be
Options
- A-13.6 eV
- B-27.2 eV
- C-54.4 eV
- D-6.8 eV
Correct answer
A. -13.6 eV
Step-by-step solution
Energy E of an atom with principal quantum number n is given by E= -13.6 n ^2 Z^2 for first excited state n =2 and for He ⁺ Z =2 aligned E & = -136 (2)^2 (2)^2 & =-13.6 eV aligned