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What do the symbols (s), (l), and (g) mean in a chemical equation?

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combustion — chemical reaction Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

In a chemical equation, the symbols (s), (l), and (g) are used to designate the physical state of the reactants and products involved in a chemical reaction. These symbols represent the following states of matter:

(s): solid1
(l): liquid1
(g): gas1

By including these notations, chemists can precisely describe the conditions of the substances participating in the reaction, such as in the synthesis of iron sulfide: $Fe(s) + S(s) \to FeS(s)$ .1