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How does a single arrow differ from a double arrow in a chemical equation?
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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 type of arrow used indicates the nature of the reaction:
- Single Arrow (): This symbol denotes an irreversible reaction, meaning the reactants are converted into products, but the products do not react to reform the original reactants under the given conditions.1
- Double Arrow (): This symbol denotes a reversible reaction. In such reactions, products can react to produce the original reactants. When these opposing reactions occur at equal rates, the system reaches chemical equilibrium, where there is no net change in the amounts of reactants and products present.2