Is fire a solid, liquid or gas?

Most flames are made of hot gas, but some burn so hot they become plasma.

30th May 2018
Is fire a solid, liquid or gas? © Getty

Asked by: Toby Graham, Shrewsbury

The nature of a flame depends on what is being burnt. A candle flame will primarily be a mixture of hot gases (air and vaporised paraffin wax). The oxygen in the air reacts with the paraffin to produce heat, light and carbon dioxide. Other materials – such as magnesium – burn much hotter, resulting in the fourth state of matter: plasma.

Is fire a solid, liquid or gas? © Raja Lockey
© Raja Lockey

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