A gaseous atom Z emits two photons when its electron cascades successively from the…
CHEMISTRY · Multi-part · AP · Chemistry · Properties of Substances and Mixtures · Properties of Substances and Mixtures
Problem
A gaseous atom Z emits two photons when its electron cascades successively from the second excited state to the first excited state and then to the ground state. The measured photon energies are 5.10eV for the first transition and 2.55eV for the second transition. Independent experiments show that removing the electron from the ground state requires 12.75eV.
(a) Determine the energies (in \text{eV}) of the first and second excited states relative to the ground state, treating the ground state as E0=0eV.
(b) Calculate the energy of the ionization limit relative to the first excited state. Comment on how this value compares with the energy you found for the second excited state.
(c) Sketch a simple energy-level diagram labeling the ground state, both excited states, and the ionization limit. Indicate the two observed photon transitions with arrows and label each with its energy.