0 votes 0 votes In an hydrogen atom $10.2 . \mathrm{eV}$ is given out as radiation when an electron is de-excited to the ground state. The principal quantum number of the excited state is ___________. Others gate1993-ec + – admin asked Sep 16, 2022 • edited Dec 1, 2023 by makhdoom ghaya admin 46.4k points 99 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.