Corrosion MCQs : This section focuses on the "Corrosion". These Multiple Choice Questions (MCQs) should be practiced to improve the Corrosion skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Which of the following is the overall reaction of rusting?
A. 2Fe(s) → 2Fe2+ + 4e–
B. O2 (g)+4H+(aq)+4e–⟶2H2O(l)
C. 2Fe(s) + O2(g) + 4H+(aq) → 2Fe2+(aq) + 2H2O(l)
D. H2O ⇌ H+ + OH–
Which of the following metal doesn’t follow linear oxidation law?
Which of the following is/are the advantages of Tafel extrapolation?
A. It can measure extremely low corrosion rates
B. It can be used for continuously monitoring the corrosion rate of a system
C. It can be used for continuously monitoring the corrosion rate of a system with high accuracy and measures extremely low corrosion rates
D. It can be performed rapidly with high accuracy
Which of the following is/are the limitations of Tafel extrapolation?
A. For reasonable accuracy, the Tafel region must be extended
B. It can be applied to systems containing one reduction process only
C. Much interference from concentration polarization
D. It can be applied to systems containing one reduction process, for reasonable accuracy the Tafel region must be extended and there will be much interference from concentration polarization
Which of the following is/are the applications of mixed-potential theory?
A. Permit prediction of complex corrosion behavior
B. To develop new corrosion prevention methods
C. To develop new rapid corrosion rate measurement
D. Permit prediction of complex corrosion behavior, to develop new corrosion prevention methods and to develop new rapid corrosion rate measurement
What is the full form of CRA?
A. Corrosion Resistant Alloy
B. Corrosion Resistant to Alloy
C. Casing Resistant Alloy
D. Casing Recovering Assistant
Which of the following metals follows logarithmic oxidation law?
D. Aluminum, copper, and iron
The corrosion rate is usually dependent at low velocity whereas at high velocities it becomes independent.
Which of the following metals results in the ignition in extreme cases?
D. Sodium, magnesium, and niobium
Which of the following metals results in the formation of volatile oxides?
C. Osmium, tungsten, molybdenum, and Vanadium
Which of the following statements is false?
A. Salt water decelerates the rate of corrosion
B. Magnesium is more active than iron
C. During galvanization, ZnCO3.Zn(OH)2 is formed which prevent further corrosion
D. Anti-rust solutions are used in car radiators to prevent rusting of iron parts of the engine
Which of the following industries uses Tafel extrapolation or linear polarization to measure low corrosion rates?
A. Nuclear industries
B. Pharmaceutical industries
C. Food processing industries
D. Nuclear, pharmaceutical and food processing industries
Which of the following mechanical properties is/are important in structural applications of metals?
A. Tensile strength
B. Yield strength
C. Ductility and Elasticity
D. Tensile strength, Yield strength, Ductility, and Fracture toughness
Which of the following metal does not corrode?
Which of the following is not essential for rusting to take place?
A. Metal (like iron)
Acidic corrosion can be found to happen in Oil and Gas production wells?
What is meant by anodic protection?
A. Accompanying the sacrificial metal with metallic structure
B. Prevention of corrosion by impressed cathodic current by supply electrons
C. Prevention of corrosion by the impressed anodic current is used to transform from active to a passive state
D. Additions of oxidizers and oxidizing agents for the formation of an oxide layer
Which of the following nickel-based alloys is/are superalloys?
A. Hastelloy C-276
B. Inconel 718
C. Hastelloy C-276, Inconel 718 and Hastelloy HX
D. Hastelloy HX
Sulphide Stress Cracking/ Hydrogen Embrittlement can’t be found in corrosion in oil and gas.
Which of the following electrochemical methods is/are used to determine the corrosion rate?
A. Tafel extrapolation
B. Linear polarization
C. Tafel extrapolation and linear polarization
D. Neither Tafel extrapolation nor linear polarization
Which of the following statements regarding corrosion is true?
A. Corrosion does not depend on the reactivity of the metal
B. Presence of impurities does not affect the rate of corrosion
C. Strains in metals affect the rate of corrosion
D. Presence of electrolytes does not affect the rate of corrosion
Which of the following is/are true regarding parabolic oxidation rate law?
A. It was proposed by C. Wagner
B. It states that square of weight loss is directly proportional to the time of exposure
C. It was proposed by C. Wagner which states that square of weight loss is directly proportional to the time of exposure and it resembles non-steady-state diffusion-controlled reactions
D. It resembles non-steady-state diffusion-controlled reactions
What does CSC mean in corrosion?
A. Calcium Stress Cracking
B. Casing Stress Cracking
C. Chromium Stress Cracking
D. Chloride Stress Cracking
Which of the following metals that are spontaneously passivated on coupling with platinum?
C. Titanium and Chromium
D. Neither titanium nor chromium
Which of the following is/are the limitations of high-temperature non-metallic materials?
A. Lack of ductility
B. Less resistance to thermal shock
C. Weldability, less resistance to thermal shock, lack of ductility and formability
D. Weldability and formability
Magnesium is used as a sacrificial metal to protect iron from rust.
What is the method of protection of iron by coating it with zinc called?
B. Cathodic protection
D. Anti-rust solutions
Which of the following is/are true regarding internal corrosion?
A. Corrosion products precipitate in the metal matrix
B. Corrosion products precipitate in the metal matrix and metals such as Fe, Ni, and Co are highly prone to internal corrosion
C. Corrosion occurs on external surfaces of metals
D. It is due to the stable corrosion products of base metals
Rusting of iron is a type of corrosion.
Which of the following is/are correct regarding linear oxidation law?
A. Weight gain per unit area of the metal is directly proportional to the exposure time
B. It is a characteristic of porous or cracked scale
C. Sodium is an example that follows linear oxidation law
D. Weight gain per unit area of metal is directly proportional to exposure time, it is characteristic of porous or cracked scale and sodium follows linear oxidation law
Which of the following is/are correct regarding the measurement of the rate of oxidation?
A. Weight loss per unit area of metal is the measure of the rate of oxidation
B. Either weight loss or weight gain per unit area of metal is the measure of the rate of oxidation
C. Weight gain per unit area of metal is the measure of the rate of oxidation
D. Neither weight loss nor weight gain per unit area of metals is the measure of the rate of oxidation
What are the types of oxidation rate laws?
A. Linear and parabolic law
B. Cubic and logarithmic law
C. Linear, parabolic and cubic law
D. Linear, parabolic, cubic and logarithmic law
Which of the following is/are correct when oxidizing agents are added to a corrosion system containing a non-passivating metal?
A. Rate of corrosion decreases after certain potential
B. Rate of corrosion increases with increase in oxidizers concentration
C. Rate of corrosion increases after certain potential
D. Results in the formation stable oxide layer
Which of the following is/are true regarding stress rupture?
A. The stress required to cause a rupture in a predetermined time at a constant temperature
B. It is important in short-term high-temperature applications
C. Stress rupture is an important mechanical property for gas turbine or rocket engines
D. The stress required to cause a rupture in short-term high-temperature applications at a predetermined time is known as stress rupture and it is an important mechanical property for gas turbines and rocket engines
Which of the following is/are correct regarding creep?
A. It is the continuous plastic elongation of metal under constant load
B. It is the high-temperature mechanical effect of a metal
C. It is the continuous plastic elongation of metal under constant load at high temperature and it can be minimized by the fraction of grain boundaries
D. It can be minimized by reducing the fraction of grain boundaries
Which of the following type of polarization has a negligible effect on velocity?
A. Concentration polarization
B. Activation polarization
C. Concentration polarization and Activation polarization
D. Neither concentration nor Activation polarization
Casing Integrity can be checked by ________
B. Temperature Survey
C. Dual Latero Log
D. Neutron Porosity
Which of the following does not cause rusting of iron?
Which of the following is/are the high melting point metals?
D. Molybdenum, tungsten, columbium, and tantalum
Diffusion-controlled oxidation can be minimized by decreasing the concentration of ionic defects in the scale.
Which of the following is not a method of prevention of corrosion?
B. Anti-rust solutions
C. Cathodic protection
Which of the following is/are correct regarding the potentiostat method?
A. It is a polarization technique that allows for controlled polarization
B. It works on controlling voltage between a working and reference electrode
C. It is a corrosion analysis method
D. It is a corrosion analysis technique method that allows for controlled polarization and it works on controlling voltage between a working and reference electrode.