Explanation:If the mass of the object stays the same but the volume of the object decreases then its density becomes greater. If the volume of the object stays the same but the mass of the object increases then its density becomes greater.
Activation energy is the energy needed to begin breaking the bonds of reactants and is denoted as option D.
<h3>What is a Reactant?</h3>
These are the substances which take part in a chemical reaction and result in the formation of the product.
The activation energy is required as it breaks the bonds of the reactant thereby resulting in the product being formed. This therefore makes it the most appropriate choice.
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