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प्रश्न
Can you store copper sulphate solutions in a zinc pot?
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उत्तर
\[\ce{E^\circ_{{Zn^{2+}/{ Zn}}}}\] = −0.76 V
\[\ce{E^\circ_{{Cu^{2+}/{ Cu}}}}\] = 0.34 V
We have to check whether the following reaction takes place or not.
\[\ce{Zn_{(s)} + CuSO4_{(aq)} -> ZnSO4_{(aq)} + Cu_{(s)}}\]
The cell can be represented as:
Zn | Zn2+ || Cu2+ | Cu
\[\ce{E^\circ_{cell} = E^\circ_{Cu^{2+}/Cu} - E^\circ_{Zn^{2+}/ Zn}}\]
= 0.34 V – (–0.76 V)
= 1.1 V
Since \[\ce{E^\circ_{cell}}\] is positive, the reaction takes place, and we cannot store CuSO4 solution in a zinc pot.
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