What would be the anode
a magnesium and zinc galvanic cell?

The magnesium is the anode of a magnesium and zinc galvanic cell.

The magnesium is the anode means the site of oxidation, where magnesium ions flow into solution. Here the electrons leave the electrode and flow through the voltmeter as they move to the zinc cathode.

While on the other hand, zinc is the cathode i.e. the site of reduction, where zinc ions flow onto the electrode in order to pick up electrons so we can conclude that magnesium is the anode of a magnesium and zinc galvanic cell.

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answer; /// the amount of material dissolved in a measure of liquid(concentration) the above statement is (true); /// good luck