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This section includes 13 Mcqs, each offering curated multiple-choice questions to sharpen your Corrosion Engineering knowledge and support exam preparation. Choose a topic below to get started.
1. |
Which of the following is/are the n-type semiconducting oxides? |
A. | CdO<sub>2</sub> |
B. | TiO<sub>2</sub> |
C. | Al<sub>2</sub>O<sub>3</sub>, CdO<sub>2</sub>, and TiO<sub>2</sub> |
D. | CoO |
Answer» D. CoO | |
2. |
Which of the following metal(s) produces metal oxide at a metal-scale interface? |
A. | Titanium |
B. | Niobium |
C. | Zirconium |
D. | Titanium, Niobium, and Zirconium |
Answer» E. | |
3. |
The relative thickness of each phase of a metallic oxide is determined by the rate of ionic diffusion through that phase. |
A. | True |
B. | False |
Answer» B. False | |
4. |
Which of the following order is correct regarding the oxides of iron starting from metallic iron to gaseous oxygen interface? |
A. | FeO, Fe<sub>2</sub>O<sub>3</sub>, and Fe<sub>3</sub>O<sub>4</sub> |
B. | Fe<sub>2</sub>O<sub>3</sub>, Fe<sub>3</sub>O<sub>4</sub> and FeO |
C. | Fe<sub>3</sub>O<sub>4</sub>, Fe<sub>2</sub>O<sub>3</sub>, and FeO |
D. | FeO, Fe<sub>3</sub>O<sub>4</sub>, and Fe<sub>2</sub>O<sub>3</sub> |
Answer» E. | |
5. |
The diffusion of either cation or oxygen ions usually controls the reaction rate of high-temperature metallic oxidation. |
A. | True |
B. | False |
Answer» B. False | |
6. |
Which of the following is/are the interface at which new metallic oxides (MO) are produced? |
A. | Metal-scale interface |
B. | Scale-gas interface |
C. | Metal-scale interface or scale-gas interface |
D. | Neither metal-scale interface nor scale-gas interface |
Answer» D. Neither metal-scale interface nor scale-gas interface | |
7. |
What is the value of the Pilling and Bed worth ratio of tungsten? |
A. | 1.21 |
B. | 3.40 |
C. | 2.60 |
D. | 0.45 |
Answer» C. 2.60 | |
8. |
Which of the following metal has a nonprotective oxide? |
A. | Cadmium (CdO<sub>2</sub>) |
B. | Copper (Cu<sub>2</sub>O) |
C. | Chromium (Cr<sub>2</sub>O<sub>3</sub>) |
D. | Silicon (SiO<sub>2</sub>) |
Answer» B. Copper (Cu<sub>2</sub>O) | |
9. |
Which of the following is/are the ideal characteristics of the passive metal oxide layer? |
A. | Good adherence and high melting point |
B. | Low electrical conductivity and low vapor pressure |
C. | Good adherence, high melting point, low vapor pressure, and low electrical conductivity |
D. | Good adherence and high vapor pressure |
Answer» D. Good adherence and high vapor pressure | |
10. |
Which of the following is/are the causes for the poor oxidation resistance of metal oxide with high Pilling and Bed worth ratio? |
A. | Large compressive stresses in the oxide |
B. | Cracking |
C. | Spalling |
D. | Large compressive stresses in the oxide, cracking and spalling |
Answer» E. | |
11. |
Which of the following is/are the characteristics of a metal oxide if the Pilling and Bed worth ratio is less than 1? |
A. | Protective |
B. | Unprotective |
C. | Unprotective and insufficient oxide |
D. | Unprotective and sufficient oxide |
Answer» D. Unprotective and sufficient oxide | |
12. |
Pilling and Bed worth proposed that oxidation resistance is related to the volume ratio of oxide and metal per grams atom of metal. |
A. | True |
B. | False |
Answer» B. False | |
13. |
Which of the following is/are the systems that are prone to high-temperature corrosion? |
A. | Gas turbines |
B. | Rocket engines |
C. | Furnaces |
D. | Gas turbines, rocket engines, and furnaces |
Answer» E. | |