Answer: Because new substances are formed.
Explanation: A chemical property is any of a material's properties that becomes evident during, or after, a chemical reaction; that is, any quality that can be established only by changing a substance's chemical identity. Once a chemical change occurs it cannot be undone due to the change in chemical identity. The creation of a new substance is not reversible.
Answer:
An increase in pressure would cause less volume and vice versa. They are inversely proportional.
Explanation:
This is due to Boyle's Law (and because an increase in pressure would increase the force on the container, however, if it's a closed container, it would burst)
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