Concrete used in road construction is reinforced using steel bars in a grid, known collectively as "rebar." After many years, rebar will begin to...

Concrete used in road construction is reinforced using steel bars in a grid, known collectively as “rebar.” After many years, rebar will begin to corrode, and the concrete will weaken. Studies are ongoing regarding the best metal to be a sacrificial anode to prevent corrosion of the rebar. Which would work better for the purpose, magnesium or zinc? Explain your answer based on the oxidation potentials for each metal.