Final answer:
The property of reactivity best explains the difference in rusting between iron and gold.
Step-by-step explanation:
The property of reactivity best explains the difference between iron and gold in terms of rusting. Reactivity refers to the tendency of a substance to undergo a chemical reaction. Iron is highly reactive and readily undergoes oxidation when exposed to oxygen and moisture, resulting in rust formation. On the other hand, gold is less reactive and does not easily undergo such chemical reactions, which is why it does not rust over time.
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