Question

Which of the following metals will have a high influence on aeration and oxidizing agents in hydrochloric acid?

(a) Copper and its alloys

(b) Nickel and its alloys

(c) Nickel-molybdenum alloys, copper, nickel and their alloys

(d) Nickel-molybdenum alloys

This question was addressed to me at a job interview.

My enquiry is from Mineral Acids topic in division Mineral Acids of Corrosion Engineering

Answer 1

Correct choice is (c) Nickel-molybdenum alloys, copper, nickel and their alloys

To elaborate: Nickel-molybdenum alloys, copper, nickel, and their alloys will have a high influence on aeration and oxidizing agents in hydrochloric acid. These materials show excellent corrosion resistance in reducing conditions but are rapidly attacked in oxidizing conditions.