What does spectroscopy measure?

Therefore, spectroscopy for physical scientists becomes the interaction of atoms and molecules with the electromagnetic spectrum. The type of spectroscopy that can be used to examine a specific atom, atomic particle, or molecule depends on two factors: (i) the characteristics of the species that absorbs light (radiation) and (ii) the quantity of absorbing species.

Because of this, spectroscopy can typically be made quantitative. Based on the strength and intensity of a sample's radiation absorption, one can infer some information about its concentration.

Spectroscopy measures the interaction between matter and electromagnetic radiation. It analyzes the absorption, emission, or scattering of light by atoms, molecules, or solids to determine their properties such as composition, structure, concentration, and physical state.