Which instrument is used to measure the intensity of light absorbed after passing through a sample solution?

The instrument used to measure the intensity of light absorbed after passing through a sample solution is a spectrophotometer. This device operates based on the principle that different substances absorb light at specific wavelengths, with the amount of light absorbed being proportional to the concentration of the absorbing species in the solution.

When a beam of light is directed through a sample in a spectrophotometer, it measures how much light is absorbed by the sample at various wavelengths. The resulting data can be used to determine the concentration of substances in the solution, making it invaluable in various fields, including chemistry and environmental science.

In contrast, while a photometer is also involved in measuring light intensity, it typically does not provide the wavelength specificity that a spectrophotometer offers. A refractometer measures how light is bent as it passes through a sample, which provides information about the concentration of dissolved substances but does not specifically account for light absorption. A chromatograph is used for separating and analyzing the components of a mixture rather than measuring light absorption directly.