Superheating

In thermodynamics, superheating (sometimes referred to as boiling retardation, or boiling delay) is the phenomenon in which a liquid is heated to a temperature higher than its boiling point, without boiling. This is a so-called metastable state or metastate, where boiling might occur at any time, induced by external or internal effects.^[1]^[2] Superheating is achieved by heating a homogeneous substance in a clean container, free of nucleation sites, while taking care not to disturb the liquid.

This may occur by microwaving water in a very smooth container. Disturbing the water may cause an unsafe eruption of hot water and result in burns.^[3]

^ Debenedetti, P.G.Metastable Liquids: Concepts and Principles; Princeton University Press: Princeton, NJ, USA, 1996.
^ Maris, H., Balibar, S. (2000) "Negative Pressures and Cavitation in Liquid Helium" Physics Today 53, 29
^ Health, Center for Devices and Radiological (2018-11-03). "Risk of Burns from Eruptions of Hot Water Overheated in Microwave Ovens". FDA.

[PDB96-1] Debenedetti, P.G.Metastable Liquids: Concepts and Principles; Princeton University Press: Princeton, NJ, USA, 1996.

[MB2000-2] Maris, H., Balibar, S. (2000) "Negative Pressures and Cavitation in Liquid Helium" Physics Today 53, 29

[:0-3] Health, Center for Devices and Radiological (2018-11-03). "Risk of Burns from Eruptions of Hot Water Overheated in Microwave Ovens". FDA.

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