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
At ORNL,Polo-Garzon and Zhang used a technique called steady-state isotopic transient kinetic analysis to measure catalyst efficiency -- the number of times a single active site converts a reactant into a product.
From Science Daily • Nov. 26, 2024
"We're looking for alternative ways to excite the reactant molecules to break thermodynamic constraints," Polo-Garzon said.
From Science Daily • Nov. 26, 2024
Doubling the concentration of a reactant increases the rate of a reaction four times.
From Textbooks • Feb. 14, 2019
"By the moons of Jupiter, we've run out of reactant fuel!"
From Stand by for Mars! by Glanzman, Louis
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.
