A researcher studying atmospheric pollutants records three absorption maxima for a sample of nitrogen dioxide (NO₂) at wavelengths 210 nm, 3.0 µm, and 0.40 cm.
(a) For each wavelength, calculate the corresponding photon energy in kJ mol⁻¹.
(b) Rank the three absorptions from highest to lowest photon energy.
(c) Assign each absorption peak to the most likely type of molecular transition (rotational, vibrational, or electronic). Provide quantitative justification for every assignment based on the energies calculated in part (a).
(d) The researcher initially labels the 3.0 µm absorption as “electronic.” Use your work from parts (a)–(c) to critique this label and propose a more accurate description, explaining your reasoning.