For which purpose would a UV spectrophotometer typically be utilized?

A UV spectrophotometer is commonly utilized to determine the concentration of various substances in a solution based on their light absorption properties. The principle behind its operation relies on the fact that different compounds absorb ultraviolet (UV) light at specific wavelengths. When a light beam passes through a sample, some of the light is absorbed, and the amount of light absorbed is directly related to the concentration of the absorbing species in that solution. This property makes UV spectrophotometry a valuable tool for quantifying biomolecules like nucleic acids, proteins, and various metabolites in biological and chemical research.

The other options involve techniques or measurements that do not align with the capabilities of a UV spectrophotometer. For example, determining the mass of a solid typically involves a balance, while measuring enzyme activity usually requires other analytical methods, possibly involving spectrophotometry but not as a direct measurement with a UV spectrophotometer. Similarly, measuring temperature changes is done with thermometers or temperature sensors, not spectrophotometric techniques. Hence, option C accurately reflects the primary function of a UV spectrophotometer.