A student constructs a galvanic cell that has a strip of lead metal immersed in a solution of 0.1M Pb(NO3)2 as one half-cell and a strip of zinc metal immersed in a solution of 0.1M Zn(NO3)2 as the other half-cell. The measured cell potential is less than zero when the positive terminal of the voltmeter is attached to the zinc strip and the negative terminal is attached to the lead strip.

Which half-cell is the anode (Pb or Zn)?

Which half-cell is the cathode?

Do the electrons flow from Zn to Pb or vice versa?

Which metal is more "active" Zn or Pb?

To determine which half-cell is the anode and which is the cathode, and to identify the direction of electron flow and the more active metal, you can analyze the given information about the measured cell potential.

The galvanic cell potential is a measure of the tendency of a redox reaction to occur. A positive cell potential indicates a spontaneous reaction, whereas a negative cell potential suggests a non-spontaneous reaction.

In this case, the measured cell potential is less than zero when the positive terminal of the voltmeter is attached to the zinc strip and the negative terminal is attached to the lead strip. A negative cell potential suggests that the reaction is non-spontaneous in the given configuration.

In a galvanic cell, the anode is the electrode where oxidation occurs, and the cathode is the electrode where reduction takes place. Oxidation involves the loss of electrons, while reduction involves the gain of electrons. Since the cell potential is negative, the spontaneous reaction is reversed in this setup. Therefore, the anode and cathode will be switched compared to the standard configuration.

Based on this information, in the given configuration:
- The strip of lead metal (Pb) is the anode.
- The strip of zinc metal (Zn) is the cathode.

When the cell potential is negative, the direction of electron flow is from the anode to the cathode. In this case, electrons flow from the lead strip (the anode) to the zinc strip (the cathode).

Lastly, comparing the reactivity or "activity" of the metals, the one that is more easily oxidized is considered more active. Since lead (Pb) is the anode where oxidation occurs, it means that lead is more active than zinc (Zn).

You need to learn to do these yourself. What do you not understand about the problem? I can help you through it but I don't want to just give you the answers.