Physical changes occur when objects or substances undergo a change that does not change their chemical composition. This contrasts with the concept of chemical change in which the composition of a substance changes or one or more substances combine or break up to form new substances.
Answer:
a bird sitting on a branch
The statement that identifies an oxidation-reduction reaction is a reaction in which oxidation numbers change (option C).
<h3>What is a redox reaction?</h3>
A redox or oxidation-reduction reaction is a chemical reaction in which some of the atoms have their oxidation number changed.
In a chemical reaction that involves oxidation and reduction, the oxidation number of the involved ions either decreases or increases.
Therefore, the statement that identifies an oxidation-reduction reaction is a reaction in which oxidation numbers change.
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