Which of the following elements readily react with oxygen to form their oxides?
Show Hint
- Au and Pt
- Ne and Ar
- Al and Cu
- Cu and Pt
The Correct Option is C
Solution and Explanation
Aluminium (Al) is highly reactive with oxygen and forms a protective layer of aluminium oxide (Al\(_2\)O\(_3\)).
Copper (Cu) also reacts with oxygen, though less vigorously, forming copper oxides (CuO and Cu\(_2\)O) over time.
Step 2: Rule out incorrect options.
Option (1): Au (Gold) and Pt (Platinum) are noble metals, known for their low reactivity and resistance to oxidation.
Option (2): Ne (Neon) and Ar (Argon) are noble gases and completely inert under normal conditions—they do not form oxides.
Option (4): Pt, as discussed, is not reactive enough to form oxides readily. Hence, the correct answer is (3) Al and Cu.
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