Home › MCQs › EEJ MAIN Chemistry › Question #7173
Back to Questions
EEJ MAIN Chemistry QUESTION #7173
Question 1
Considering the ground state energy of a hydrogen atom is $-13.6 \text{ eV}$, what would be the energy of the second excited state for a $He^{+}$ ion in eV?
  • $-54.4$
  • $-3.4$
  • $-6.04$✔️
  • $-27.2$
Correct Answer Explanation
For hydrogen-like species, $E_{n} = -13.6 \frac{Z^{2}}{n^{2}} \text{ eV}$.
  • For $He^{+}$, atomic number $Z = 2$.
  • The second excited state corresponds to $n = 3$.
  • $E_{3} = -13.6 \times \frac{2^{2}}{3^{2}} = -13.6 \times \frac{4}{9}$
  • $E_{3} \approx -6.04 \text{ eV}$