Final answer:
Metals react most readily with oxygen, a process known as oxidation, because it universally happens under natural conditions, whereas not every metal reacts with water or acid, and certain specific conditions may be necessary for those reactions to occur.
Step-by-step explanation:
Metals react most easily with oxygen compared to water and acid. This is primarily due to the fact that the reaction between metals and oxygen, also known as oxidation, is a universal process that occurs readily in nature, giving rise to oxides of metals. On the contrary, not all metals react with water and acid. For instance, metals like gold, platinum, and silver do not react with water or acid at all. Furthermore, even those metals that do react with water or acid may not always do so easily due to the necessity for certain conditions such as heat or specific concentrations of the water or acid.
One key example of metal reacting with oxygen is iron. In the presence of moisture and oxygen, iron undergoes a chemical process known as rusting, where it gets converted into iron oxide, a process that happens readily and easily.
In conclusion, metals demonstrate the fastest and most extensive reactivity with oxygen, making it the substance with which metals react most easily.
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