Question

zinc can liberate in hydrogen but copper cannot displace in hydrogen

Answer 1

In the reactivity series, zinc is plaved above hydrogen while copper is placed below it. Thus the reavtivity of zinc Is hogher than Hydrogen while the reavtivity of copper is less than Hydrogen. An element having more rwactivity can displace an element having low reactivity from a compound. Hence zinc can displace Hydrogen but Copper cannot.
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