Final answer:
Absorption spectroscopy primarily provides qualitative information about the functional groups in a molecule because different groups absorb radiation at characteristic frequencies. It does not give data on molecular weight, concentration, or pH.
Step-by-step explanation:
The qualitative information gained from absorption spectroscopy is typically related to the functional groups within a molecule. By observing which wavelengths a molecule absorbs, and to what extent it absorbs them, we gain information about the nature of the energetic transitions that a molecule undergoes, providing insights into its molecular structure. Absorption spectroscopy can tell us about the presence of certain functional groups due to their characteristic absorption frequencies. For instance, the carbonyl group in a ketone often absorbs in a distinct frequency range, allowing us to identify its presence in a sample. Additionally, different isotopes in a molecule, like hydrogen chloride (HCl), will affect the absorption spectrum due to changes in the moment of inertia and vibrational energy levels, influencing the separation between peaks.
On the other hand, absorption spectroscopy does not provide information about the molecular weight, concentration, pH, or atom-specific properties such as atomic radius, electronegativity, first ionization energy, and boiling point.