1. Intergrannular corrosion of light 18-8 stainless steel can not be prevented by
2. Which of the following metals is highest noble in the Galvanic series?
3. Difficult to monitor and very dangerous form of corrosion
4. Based on the standard galvanic series, select the correct sequence of metals in the increasing order of anodic behaviour:
5. Corrosion of metals involves
6. Match the form of corrosion in Group 1 with the typical examples in Group 2.
Group 1
Group 2
P. Filiform corrosion
1. Austenitic stainless steel in chloride environment
Q. Crevice corrosion
2. Nut bolt with gasket
R. Galvanic corrosion
3. Painted food cans
S. Stress corrosion cracking
4. Steel studs in copper plate
| Group 1 | Group 2 |
| P. Filiform corrosion | 1. Austenitic stainless steel in chloride environment |
| Q. Crevice corrosion | 2. Nut bolt with gasket |
| R. Galvanic corrosion | 3. Painted food cans |
| S. Stress corrosion cracking | 4. Steel studs in copper plate |
7. The difference in reversible potential between oxygen reduction reaction and hydrogen evolution reaction of any pH in an aqueous electrolyte is . . . . . . . . volt.
[Given, standard reduction potentials for hydrogen evolution reaction, $$\frac{{{E^ \circ }2{H^ + }}}{{{H_2}}} = OV,SHE$$ and oxygen reduction reaction : $$\frac{{{E^ \circ }{O_2}}}{{4OH}} = 0.4V,SHE.$$ Also PH2 = PO2 = 1 atm]
[Given, standard reduction potentials for hydrogen evolution reaction, $$\frac{{{E^ \circ }2{H^ + }}}{{{H_2}}} = OV,SHE$$ and oxygen reduction reaction : $$\frac{{{E^ \circ }{O_2}}}{{4OH}} = 0.4V,SHE.$$ Also PH2 = PO2 = 1 atm]
8. Zinc rod is immersed in dilute HCl (pure). If a very small amount of FeCl3 is added to the solution, the corrosion rate of zinc
9. Which of these metals can not be electroplated from aqueous electrolyte?
10. The oxygen activity in a liquid metal can be-measured by a concentration cell using stabilised zirconia electrolyte PO2(1) | ZrO2 based solid electrolyte | PO2(2)
Where, PO2(1) is the reference oxygen pressure and PO2(2) is the oxygen pressure in equilibrium with liquid metal. If, F is Faraday constant, the EMF of the cell is equal to
Where, PO2(1) is the reference oxygen pressure and PO2(2) is the oxygen pressure in equilibrium with liquid metal. If, F is Faraday constant, the EMF of the cell is equal to