noun
Etymology
Origin of reactant
Explanation
A reactant is a substance that changes in a chemical reaction. Vinegar and baking soda are reactants — when you mix them together, they bubble up and make really good lava for a model volcano. Reactants usually hang around the chemistry lab, but the concept isn't difficult if you think about the word react. When people react, they do something such as laugh at a joke or cry at sad news. In chemistry, reactants are part of something happening too: if two chemicals bond when mixed together, or if one dissolves, they are reactants. Any kind of chemical reaction involves reactants.
Vocabulary lists containing reactant
Chemistry - Introductory
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Chemical Reactions - Introductory
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Chemistry - High School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
"We were able to vary the behavior and effective size of the ultrasmall pores by changing the composition and pH of the reactant solutions," reports Tomoji Kawai, senior author.
From Science Daily ● Feb. 19, 2026
Once the temperature is sufficiently low, the concentration of the reactant gases on the catalyst surface increases and the reaction picks up speed again.
From Science Daily ● Oct. 5, 2023
That is, as the temperature of the reaction goes up due to its heat production, the reactant gases lose contact with the catalyst surface and their reaction slows down, which reduces the temperature.
From Science Daily ● Oct. 5, 2023
An alternative approach to identifying the limiting reactant involves comparing the amount of product expected for the complete reaction of each reactant.
From Textbooks ● Feb. 14, 2019
No matter what distance or reactant I assume, nothing we know will fit.
From Masters of Space by Berry, Robert Lee
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
