Can you store copper sulphate solutions in a zinc pot?
No, copper sulphate solution cannot be stored in a zinc pot.
According to the standard electrode potentials, zinc has a negative standard electrode potential of -0.76 V for the reaction: Zn²⁺(aq) + 2e⁻ → Zn(s). This negative value indicates that zinc is more reactive and has a greater tendency to lose electrons compared to copper.
When copper sulphate solution is stored in a zinc pot, zinc will oxidise and lose electrons, while Cu²⁺ ions will reduce and gain electrons. The reaction occurs as: Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s). Thus, zinc displaces copper from the solution, forming zinc sulphate and depositing copper metal. Therefore, storage is not possible as the zinc pot will gradually dissolve.
Explanation
This question tests understanding of electrochemical series and displacement reactions. The textbook context provides the standard electrode potential of Zn²⁺/Zn as -0.76 V. A negative electrode potential means the metal has a greater tendency to oxidise (lose electrons). Since zinc has a more negative reduction potential than copper, zinc is more reactive and can displace copper from its salt solution. This is the same principle used in the Daniell cell mentioned in the context, where zinc dissolves at the anode and copper deposits at the cathode.
Solution Steps
Step 1: Identify the standard electrode potential of Zn²⁺/Zn = -0.76 V from the context
Step 2: Compare reactivity - more negative potential means greater tendency to oxidise
Step 3: Apply displacement reaction principle - Zn displaces Cu from CuSO₄ solution
Step 4: Conclude that zinc pot will corrode, making storage unsuitable