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प्रश्न
Zinc liberates hydrogen gas when reacted with dilute hydrochloric acid whereas copper does not. Explain why?
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उत्तर
Zinc (Zn) is placed above hydrogen in the activity series. It therefore, displaces hydrogen from dilute HCl.
`"Zn"("s") + 2"HCl"("aq") -> "ZnCl"_2("aq") + "H"_2("g")`
Copper is placed below hydrogen and therefore, does not react with dilute HCl.
Cu (s) + HCl (aq) → No action.
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