As you proceed down the periodic table, the metallic character becomes stronger. This is because as the atomic radius increases, there is less attraction between the nucleus and the valence electrons due to the greater distance between them, making electrons simpler to shed.
Answer: as copper has lower electrode potential value than hydrogen, it could be reduced by hydrogen.
Explanation: hydrogen has zero reduction potential while Cu has +0.34V and Al has -1.66 V .
SO in electrochemical series who has most negative or less reduction potential value tends to be a good reducing agent than the other.
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Answer:
An atom is composed of them
Explanation: