Government Polytechnic, Malvan Chapter 2: Metal Corrosion MCQ (2024-2025) PDF

Government Polytechnic,Malvan Question Bank (2024-2025) Year : First (I- SEM) Courses: CO/CE/EE/EX/ME/FC - 1K Subject: Basic Chemistry (311305) CHAPTER 2: ME...

Government Polytechnic,Malvan Question Bank (2024-2025) Year : First (I- SEM) Courses: CO/CE/EE/EX/ME/FC - 1K Subject: Basic Chemistry (311305) CHAPTER 2: METAL CORROSION IT’S PREVENTION AND ECTROCHEMISTRY 1. Corrosion is the example of…… (a) Oxidation (b) Reduction (c) Electrolysis (d) Erosion 2. The following factors play vital role in corrosion process…… (a) Temperature (b) pH (c) Both (a) and (b) (d) None of these 3. Corrosion can be prevented by…….. (a) Alloying (b) Tinning (c) Galvanizing (d) All of the above 4. Oxidation-reduction reaction involves….. (a) Protons (b) Neutrons (c) Electrons (d) None of the above 5. When a buried pipeline is protected from a corrosion by connecting to magnesium blocks ,then it is called as…. (a) Galvanizing (b) Sacrificial cathodic protection (c) Sacrificial anodic protection (d) Any of these 6. During wet corrosion….. (a) Anodic part undergoes corrosion (b) Cathodic part undergoes corrosion (c) Both parts undergo corrosion (d) none of the above 7. Wet corrosion can occur only if……. (a) Oxygen is present in contact with the metal (b) Air is present in contact with the metal (c) Liquid medium is in contact with the metal (d) none of the above are present 8. During wet corrosion in acidic environment, (a) Oxygen evolution occurs (b) Oxygen absorption occurs (c) Hydrogen evolution occurs (d) Hydrogen absorption occurs 9. During galvanic corrosion, most noble metal acts as…. (a) Anode (b) Cathode (c) Anode and cathode (d) Corroding metal 10. In waterline corrosion, the maximum amount of corrosion takes place…. (a) Along the line just above the level of water meniscus (b) Along a line at the level of water minus (c) Along the line just below the level of water minus (d) the bottom of the vessel 11. Galvanizing is the process of coating iron with….. (a) Tin (b) Zinc (c) Copper (d) Nickel 12. Anodic coating protects the underline metal…. (a) Due to its noble character (b) sacrificially (c) Due to both (a) and (b) (d) None of the above 13. Difficult to monitor and very dangerous form of corrosion is…. (a) Galvanic (b) Pitting (c) Crevice (d) Stress 14. Food stuff containers should not be… (a) Galvanized (b) Electroplated (c) Tinned (d) All of these 15. The chemical composition of rust is…. (a) Fe2O3. H2O (b) Fe3O4. XH2O (c) Fe2O3. XH2O (d) Fe3O4. H2O 16.Pitting corrosion is due to… (a) Breaking of the oxide layer of the metal (b) Acidity (c) Stress in the metal (d) All of the above 16. The metal at the top of electrochemical series is…. (a) Most stable (b) Most Nobel (c) Less active (d) most active 17. Differential aeration corrosion takes place due to…. (a) Difference in air concentration (b) Difference in air and humidity concentration (c) Hydrogen evolution (d) oxygen absorption 18.Which oxide film is more protective? (a) Porous (b) Non-porous (c) Volatile (d) None of the above 19.The metals which do not form adherent oxide film on the metal surfaces are….. (a) Gold and Silver (b) Iron and Steel (c) Copper and Aluminum (d) Nickel and Titanium 20.The corrosion by the mechanism of oxygen absorption can occur if….. (a) Electrolyte is neutral or alkaline (b) Electrolyte is neutral or acidic (c) Electrolyte is neither neutral nor acidic (d) none of the above 21. During differential aeration type corrosion, the corrosion… (a) Occurs at more oxygenated part (b) Occurs at less oxygenated part (c) Is uniform throughout (d) Occurs at the cathodic part 22. In acidic environment, the electrochemical corrosion occurs with the replacement of H+ ion by the metal….. (a) Fe (b) Cu (c) Fe and Cu (d) None of the above 23.The process of attaching more reactive metal to an iron object that will act as an anode is called….. (a) Cathodic protection (b) Erosion protection (c) Sacrificial protection (d)None of these 24. Which oxide film is non-protective? (a) Stable porous (b) Stable non-porous (c) Volatile (d) Both (a) and (c) 25.The corrosion of metal by galvanic cell action takes place on account of the impurities of….. (a) Nobel metal (b) Less active metal (c)More active metal (d) None of these 26. Corrosion of a metal surrounded by moist air or natural solution containing dissolved oxygen is an example of….. (a) Galvanic cell corrosion (b) Dry cell corrosion (c) Concentration cell corrosion (d) None of the above 27. When two dissimilar metals are electrically connected, then more active metal becomes… (a) Cathode and gets protected (b) Cathode and undergoes corrosion (c) Anode and gets protected (d) Anode and undergoes corrosion 28. A steel screw in a brass marine hardware corrodes due to… (a) Galvanic corrosion (b) Pitting corrosion (c) Oxide film formation (d) Oxidation corrosion 29. Corrosion can be prevented by…. (a) Using pure metal (b) Alloy formation (c) Cathodic protection (d) All of the above 30. In the corrosion process by evolution of hydrogen… (a) The cathodes have large area than anodes (b) The anodes have larger area than cathodes (c) The area of anodes and cathodes are same (d) none of the above