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.
By adjusting the chemical composition and pH of the reactant solutions, they altered both the size and properties of the ultrasmall openings.
From Science Daily ● Feb. 19, 2026
This process involves destabilizing one of the aromatic rings in quinoline, using light and sometimes a catalyst, so that a reactant can 'latch' onto the ring, forming the target compound.
From Science Daily ● Jun. 19, 2024
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
An equation is balanced when the same number of each element is represented on the reactant and product sides.
From Textbooks ● Feb. 14, 2019
On the morning of the fourth day he walked into the radar bridge where Roger and Alfie had been working steadily for seventy-two hours on an electronic fuse to trigger the reactant units.
From Danger in Deep Space by Louis Glanzman
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.
