What does the term 'chromatography' generally refer to?

The term 'chromatography' refers to a technique for separating components in a mixture, which is fundamental in analytical chemistry. This process is based on the principle that different substances in a mixture interact differently with a stationary phase and a mobile phase. As the mobile phase moves through the stationary phase, components in the mixture travel at different rates, allowing them to be separated from one another.

This technique is versatile and can be applied to liquids (liquid chromatography) or gases (gas chromatography), depending on the state of the phases used. Chromatography can be used for various applications, including purifying compounds, analyzing complex mixtures, and identifying substances in a sample, making it an essential tool in chemical analysis and various fields such as biotechnology, pharmaceuticals, and environmental testing.

The other options do not encapsulate the essence of chromatography. Measuring light absorption relates to spectrophotometry, filtering solid materials is associated with filtration techniques, and synthesizing chemical compounds refers to chemical synthesis processes, which are distinct from the separation processes involved in chromatography.