The direction of electron flow is from the Zn electrode to the Pb electrode.
b. The balanced half-reaction equation for the oxidation of Zn in half-cell 1 is: Zn(s) → Zn2+(aq) + 2e−
c. Oxidation will occur in half-cell 1.
When switch S is closed, electrons will flow from the more active metal (Zn) to the less active metal (Pb). This is because the Zn atoms have a lower ionization energy and are therefore more likely to lose electrons.
The electrons flow through the external circuit to the Pb electrode, where they reduce Pb2+ ions to Pb atoms. The overall reaction is:
Zn(s) + Pb2+(aq) → Zn2+(aq) + Pb(s)
So, the direction of electron flow is from the Zn electrode to the Pb electrode.
c. Oxidation is the loss of electrons, so it will occur in the half-cell where electrons are flowing away. so, electrons are flowing away from the Zn electrode, so oxidation will occur in half-cell 1.