Corrosion MCQs

By: Prof. Dr. Fazal Rehman | Last updated: May 23, 2025

1. To produce ______ coloured hydrated ferric oxide iron undergoes a corrosion process.
(A) Red
(B) Brown
(C) Green
(D) Blue

2. The estimated amount of wasted iron due to the corrosion process is____ of its annual production.
(A) 1
(B) 1/2
(C) 1/4
(D) 1/8

3. ______ more energy than the nickel cadmium batteries is the advantage of the nickel-metal hydrated batteries.
(A) 100%
(B) 50%
(C) 75%
(D) 25%

4. Cells are composed of three parts of zinc used as _______ in zinc-air cells.
(A) Anodes
(B) Cathode
(C) Based on the half cell
(D) Can’t be said

5. The zinc-air batteries contain ___ emf of their anodes.
(A) -1V
(B) -1.25V
(C) 1V
(D) 1.25V

6. The working voltage of the battery is ________ is a drawback of this battery because of the internal losses.
(A) Higher
(B) Lower
(C) Moderate
(D) Not considerable

7. ______ voltage of electricity is present in nickel metal hydrated batteries which is a low voltage.
(A) 1V
(B) 1.2V
(C) 1.3V
(D) 1.4V

8. Reverse process of __________ is corrosion.
(A) Metal extraction
(B) Metal production
(C) Metal heating
(D) Metal moulding

9. Which one of the following does not lose during corrosion?
(A) Malleability
(B) Ductility
(C) Conductivity
(D) Colour

10. The zinc-air batteries contain ___ emf of their cathode.
(A) 0.1V
(B) 0.2V
(C) 0.3V
(D) 0.4V

11. Metals are not converted into _____ in corrosion, as a result of decay.
(A) Oxides
(B) Hydroxides
(C) Carbonates
(D) Peroxides

12. The metals exist in nature in the form of their minerals or ores except ____
(A) Gold
(B) Silver
(C) Copper
(D) Iron