The first three energy levels \(E(\mathrm{eV})\) of the fictitious element \(\mathrm{X}\) are \(\ldots . . \ldots\) shown in Figure P29.56.

a. What wavelengths are observed in the absorption spectrum of element X? Give your answers in \(\mathrm{nm}\).

b. State whether each of your wavelengths in part a corresponds to ultraviolet, visible, or infrared light.

c. An electron with a speed of \(1.4 \times 10^{6} \mathrm{~m} / \mathrm{s}\) collides with an atom of element X. Shortly afterward, the atom emits a \(1240 \mathrm{~nm}\) photon. What was the electron's speed after the collision? Assume that, because the atom is so much more massive than the electron, the recoil of the atom is negligible.

Transcribed Image Text:

E (eV) 0 =3 -2.0 11-2 -3.0 n= | -6.5 FIGURE P29.56