Learn Chemistry: Glossary


A glossary for Learn Chemistry explaining the meaning of chemistry terms used within this site.

Type of Activity

group work, working independently



Age Group

16 to Undergraduate
Term Definition
Calibration (thermometers) To ensure accurate temperature readings (for example when measuring melting points) thermometers are often calibrated by measurement of melting points of pure compounds. A graph of measured melting points against actual ones can then be used to correct the thermometer.
Capillary (tubes) Thin walled tubes of a small diameter. These can be sealed at one end for use in melting point determinations or they can be 'drawn out' to make micropipettes for spotting TLC plates.
Chromophore A group which will absorb radiation in the visible or UV spectrum. Compounds containing chromophores can be visualised on developed TLC plates under UV light providing the plate has been pre-treated with a suitable fluorescing agent.
Clear solution A liquid that is free of any solids or suspended material. A clear solution may be coloured.
Colourless Any material that has no colour (as opposed to white).