The reaction between ethanol C2H5OH and water H2O is a chemical reaction and is exothermic.
Option A is correct.
A chemical reaction is a rearrangement between the ions and molecules of a substance. For a chemical reaction to take place, bonds are broken in the reactants and new bonds are formed in the products.
The chemical reaction between ethanol and water is;
[tex]\mathbf{C_2H_5OH + H_2O \to C_2H_4 + 2H_2O}[/tex]
Therefore, we can conclude that A chemical reaction occurs, as evidenced by the volume of the resultant mixture being less than the total volume of the initial components.
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