Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

(show all your works and make sure that you answer all questions appear in the p

ID: 1015098 • Letter: #

Question

(show all your works and make sure that you answer all questions appear in the picture below)

(0 Which of the following metals are suitable for use as sacrificial anodes to peotect 10 against corrosion of underground iron pipes any are act suitable, explain why Au (gh Aner the 1930s, chromium replaced nickel for corrosion resistance and appearance on car bumpers and brim. How does chromium protect steel from comosion (50 pts) Define each of the following terms: (al Electrochemical coll Galvanic voltaic cell Fuel cell aka flow battery) Electrolytic cell

Explanation / Answer

question f: Sacrificial anode in cathode protection is a suitable technique used for protecting a metal from the corrosion. In cathode protection, it is know that, sacrificial anode will be a metal which will have less standard reduction potential (the tendency of the chemical species to gain electron) than the metal which need to be protected from corrosion and hence more easy to be oxidized/corroded.

The metal listed in the question and their standard reduction potential are tabulated below:

Metal

standard reduction potential

Gold (Au),

+1.68

Cadmium (Cd)

-0.403

Co (Cobalt)

-0.28

Chromium (Cr)

-0.74

Manganese (Mn)

-1.18

Zinc (Zn)

-0.763

Iron (Fe)

-0.44

In the above table, the metal having standard reduction potential less than iron are Manganese (Mn), Zinc (Zn), and Chromium (Cr) hence can be used as sacrificial anode to protect iron from corrotion. The most preferential being manganese and Zinc as they have the lesser standard reduction potential compared to iron.

question g: the standard reduction potential of chromium is less than nickel and hence can be a replacement for nickel to be used as corrotion resistant material (sacrificial anode).

Metal

standard reduction potential

Gold (Au),

+1.68

Cadmium (Cd)

-0.403

Co (Cobalt)

-0.28

Chromium (Cr)

-0.74

Manganese (Mn)

-1.18

Zinc (Zn)

-0.763

Iron (Fe)

-0.44