chemical change

Chemical Changes are the changes in a substance through chemical reactions. The chemical reactants form a new product with equal mass. For example, placing a pot of water on a hot stove element causes a change in temperature and gas to be released (water vapor) but a chemical change did not take place. It was simply a physical change or a change of state. An example of a chemical change is a burning log.A chemical change is when matter changes because the substance is changed into a different substance. An example of a chemical change is paper, ash, smoke caused by burning and/or combustion.
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Noun
1. (chemistry) any process determined by the atomic and molecular composition and structure of the substances involved
(synonym) chemical process, chemical action
(hypernym) natural process, natural action, action, activity
(hyponym) acylation
(classification) chemistry, chemical science

 Say it 
Compare with physical change. A chemical change is a dissociation, recombination, or rearrangement of atoms.