For the following pairs of alloys that are coupled in seawater, predict the possibility of corrosion; if corrosion is probable, note which metal/alloy will corrode. (a) Aluminum and cast iron (b) Inconel and nickel (c) Cadmium and zinc (d) Brass and titanium (e) Low-carbon steel and copper

Look up the standard electrode potential for each metal or alloy in the pair. This information is available in standard references, such as a chemistry textbook, or reliable online resources. The values are as follows (in volts): - Aluminum (Al): -1.66 - Cast iron (Fe): -0.44 - Inconel (most common alloy contains Ni, Cr, and Mo): approximately -0.30 (since it is mainly made of nickel) - Nickel (Ni): -0.25 - Cadmium (Cd): -0.40 - Zinc (Zn): -0.76 - Brass (alloy of Cu and Zn, where Cu is the dominant metal): approximately 0.34 - Titanium (Ti): -1.63 - Low-carbon steel (also considered as Fe): -0.44 - Copper (Cu): 0.34

Determine which metal/alloy has a more negative standard electrode potential in each pair. This will help us identify which one will corrode, acting as the anode. (a) Aluminum and cast iron - Aluminum (Al): -1.66 - Cast iron (Fe): -0.44 Aluminum has a more negative electrode potential, so it will corrode. (b) Inconel and nickel - Inconel: approximately -0.30 - Nickel (Ni): -0.25 The difference in electrode potential is quite small, so the probability of corrosion is very low. However, if corrosion occurs, Inconel will corrode due to its slightly more negative potential. (c) Cadmium and zinc - Cadmium (Cd): -0.40 - Zinc (Zn): -0.76 Zinc has a more negative electrode potential, so it will corrode. (d) Brass and titanium - Brass: approximately 0.34 - Titanium (Ti): -1.63 Titanium has a more negative electrode potential, so it will corrode. (e) Low-carbon steel and copper - Low-carbon steel (Fe): -0.44 - Copper (Cu): 0.34 Low-carbon steel has a more negative electrode potential, so it will corrode.

Summarize the corrosion probability and the corroding metal/alloy for each pair: (a) Aluminum and cast iron: Corrosion is probable, and aluminum will corrode. (b) Inconel and nickel: Corrosion is unlikely; however, if it occurs, Inconel will corrode. (c) Cadmium and zinc: Corrosion is probable, and zinc will corrode. (d) Brass and titanium: Corrosion is probable, and titanium will corrode. (e) Low-carbon steel and copper: Corrosion is probable, and low-carbon steel will corrode.