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reaction
Definition
A reaction is when something happens to something else. In science, a reaction is when two or more substances interact with each other and change into new substances.
For example, when you mix baking soda and vinegar, they react and form carbon dioxide gas. The baking soda and vinegar are the reactants, and the carbon dioxide gas is the product.
Reactions can be fast or slow. The reaction between baking soda and vinegar is fast, but the reaction between iron and oxygen is slow.
Reactions can be exothermic or endothermic. An exothermic reaction releases heat, while an endothermic reaction absorbs heat.
Reactions can be reversible or irreversible. A reversible reaction can go back to the reactants, while an irreversible reaction cannot.
How can the word be used?
The patient's reaction to the medication was allergic.
Different forms of the word
Noun:
- a response to a situation or event.
- a chemical or physical change brought about by the interaction of two or more substances.
- a feeling or opinion that is the opposite of another feeling or opinion.
Etymology
The word "reaction" comes from the Latin word "reactio", which means "to act back".
The first recorded use of the word "reaction" in English was in the 14th century.
Question
What is a reaction?