Question

The maximum energy is possessed by an electron, when it is present

• A. in nucleus
• B. in ground energy state
• C. in first excited state
• D. at infinite distance from the nucleus

Answer 1

Answer: (D)

Key Idea The energy of electron is given by
$E_n=-\frac{13.6Z^2}{n^2}eV/atom$
where $Z$ is atomic number.
$n$ is number of orbits.
$E_n\propto \left[-\frac{1}{n^2}\right]$
Hence, as the value of $n$ increases, energy of the electron also increases. Therefore, when $n$ becomes infinite, energy also becomes infinite. Hence, due to this reason the maximum energy possessed by an electron, when it is present at infinite distance from the nucleus.