Applied Chemistry Multiple Choice Questions on “Corrosion”.
1. In corrosion, as a result of decay, the metals are not converted into __________
a) Oxides
b) Hydroxides
c) Carbonates
d) Peroxides
Answer: d
Clarification: In corrosion, as a result of decay the metals are not converted into peroxide. They are converted into the oxides, hydroxides, carbonates and sulphides.
2. The metals except ________ exist in nature in the form of their minerals or ores.
a) Gold
b) Silver
c) Copper
d) Iron
Answer: a
Clarification: Most of the metals except gold and platinum exist in nature in the form of their minerals or ores, in the stable combine forms as oxide, chlorides, etc.
3. Iron undergoes corrosion to produce __________ coloured hydrated ferric oxide.
a) Red
b) Brown
c) Green
d) Blue
Answer: b
Clarification: Iron undergoes corrosion to produce the brown coloured hydrated ferric oxide which is nothing but rust on the surface of the metal.
4. The corrosion is the reverse process of ____________
a) Metal extraction
b) Metal production
c) Metal heating
d) Metal moulding
Answer: a
Clarification: The corrosion is the reverse process of the metal extraction. In the pure form, metal possess the engineering properties like malleability, ductility, etc.
5. Which of the following is not lost during corrosion?
a) Malleability
b) Ductility
c) Conductivity
d) Colour
Answer: d
Clarification: Colour of the metal is not lost during the corrosion. The physical properties of the metal like Malleability, ductility and conductivity are lost.
6. The amount of iron wasted by corrosion each year is estimated about _________ of its annual production.
a) 1
b) 1/2
c) 1/4
d) 1/8
Answer: c
Clarification: The amount of the iron wasted yearly is about 1/4 of its annual production. The iron is lost by forming its compounds in the process of corrosion.
7. Nickel metal hydrated batteries having the low cell voltage of __________
a) 1V
b) 1.2V
c) 1.3V
d) 1.4V
Answer: b
Clarification: Nickel metal hydrated batteries are having very low cell voltages. It is having a voltage of 1.2V.
8. The advantages of the nickel metal hydrated batteries are having _________ more energy than the nickel cadmium batteries.
a) 100%
b) 50%
c) 75%
d) 25%
Answer: c
Clarification: The advantages of the nickel metal hydrated batteries are having 50% more energy than the nickel cadmium batteries.
9. In zinc-air cells are composed of three parts of zinc used as ___________
a) Anode
b) Cathode
c) Based on the half cell
d) Can’t be said
Answer: a
Clarification: Zinc-air cells are composed of three parts of zinc used as an anode, an air electrode is used as the cathode.
10. The drawback of this battery is the working voltage of battery is _________ due to the internal losses.
a) Higher
b) Lower
c) Moderate
d) Not considerable
Answer: b
Clarification: The drawback of this battery is the working voltage of battery is lower due to the internal losses in the zinc-air batteries.
11. The emf of the anode in zinc-air batteries is ___________
a) -1V
b) -1.25V
c) 1V
d) 1.25V
Answer: b
Clarification: The electromotive force of the anode in zinc-air batteries is -1.25. The anode is having negative potential.
12. The emf of the cathode in the zinc-air batteries is __________
a) 0.1V
b) 0.2V
c) 0.3V
d) 0.4V
Answer: d
Clarification: The electromotive force of the cathode of the zinc-air batteries is 0.4V. The cathode has the positive potential and the oxygen acts as the cathode.