Chemistry stuff.

Question

One side of a Galvanic cell has Ag+ becoming Ag. Is this the anode or cathode of the cell? Are the electrons flowing to this electrode or from it? In the salt bridge, are positive or negative ions flowing towards this side of the cell?

Answer 1

Since Ag+ is becoming Ag, the silver is going under reduction (gaining an electron). Now remember that Reduction happens at the Cathode and Oxidation at the Anaode. Easy way of memorizing this is thinking consonants match together and the vowels match together (Reduction/Cathode, Oxidation/Anode). This means that this example is at the cathode.

When it comes to the flow of electrons remember that electrons flow from negative to positive. If you look at the half reactions, the oxidation half-reaction will have a lower E^o than the reduction half-reaction, therefore electrons will travel from the Anode to the Cathode.

A main function of a salt bridge is to keep a balance of charge in both the anode and cathode. In order for the Ag+ to reduce into Ag, it needs negative ions flowing towards it.