reaction

definition: 
a reply; a change that occurs when substances are mixed
sentence: 
Scientists explore the origins of energy in chemical reactions using experimental quantum chemistry.
Reactions in solids tend to be much more complex than those in liquids, where molecules quickly diffuse into a uniform mixture.
difficulty: 
very easy
toefl frequency: 
3
toefl classification: 
adverb: 
reactively
adjective: 
reactive
adverb sentence: 
adjective sentence: 
verb: 
react
verb sentence: 
noun: 
reaction
noun sentence: