Final answer:
Decreasing the size of a substance can increase the rate of reaction due to increased surface area.
Step-by-step explanation:
False. Decreasing the size of a substance in a chemical reaction increases its surface area, which can lead to an increased rate of reaction. This is because a larger surface area provides more opportunities for particles to collide, resulting in more frequent and successful collisions. For example, consider the reaction between a solid metal and an acid. If the metal is finely powdered rather than in large chunks, the reaction rate will be faster because the acid molecules have a larger area to interact with.
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