A typical Galvanic Cell, say a Daniell cell, consitsts of two separate beaker, one containing Zn rod dipped inside aq $\ce{ZnSO4}$ and the other beaker containing Cu rod dipped inside $\ce{CuSO4}$. Does it matter what electrolyte we dip the metal in?
If we change the electrolyte of the beaker containing Zn rod to say $\ce{AgNO3}$. I would expect a displacement reaction to take place where a redox reaction occur between the Zinc rod and the Ag+ ions. No electrons will flow through the external wire. What if I replace the electrolyte with a solution of a metal that is less reactive then the metal dipped in? eg. $\ce{NaCl}$, $\ce{MgCl2}$, $\ce{KCl}$(aq). Would my cell still work?
Also, I don't understand the need of a porous pot OR salt bridge in a galvanic cell. Why would it matter if the solutions are mixed together? Why not just have one single beaker, containing an electrolyte $\ce{KCl}$(aq), and have the two different metals dipped into it. In fact, if the solutions are mixed together, there will not even be unbalance charge accumulation, and the porous pot/salt bridge would not be necessary?
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