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What does the arrow in a chemical equation represent?
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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 arrow serves as a symbol indicating the direction and nature of the transformation from reactants to products. Specifically, it signifies that the reactants "form" or "yield" the products.1
The type of arrow used provides further information about the reaction:
- Single arrow (): Denotes an irreversible reaction, where reactants are converted into products.2
- Double arrow (): Denotes a reversible reaction.2
By convention, the reactants are placed on the left side of the arrow, and the products are placed on the right.2