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Only One Option Correct Type
This section contains 17 multiple choice questions. Each question has four choices (a), (b), (c) and (d), out of which ONLY ONE is correct
Q.
In corrosion of iron
  • a)
    an electrochemical (galvanic cell) is formed in which Fe acts as anode and where O2 is reduced, is the cathode
  • b)
    electrons flow from anode to cathode through the metal while ions flow through the water droplets
  • c)
    dissolved O2 oxidises Fe2+ to Fe3+  before it is deposited as rust (Fe2O3.H2O) 
  • d)
    All the above are observed
Correct answer is option 'D'. Can you explain this answer?
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Only One Option Correct TypeThis section contains 17multiple choice qu...

(b) Electrons flow from anode to cathode-correct.
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Only One Option Correct TypeThis section contains 17multiple choice qu...
Explanation:
Corrosion of iron is a common phenomenon that occurs when iron comes in contact with oxygen and moisture. It is an electrochemical process involving the formation of a galvanic cell. Let's understand each option in detail:

a) An electrochemical (galvanic cell) is formed in which Fe acts as the anode and O2 is reduced at the cathode:
- In the presence of moisture, iron reacts with oxygen to form iron oxide (rust). This reaction involves the transfer of electrons from the anode (iron) to the cathode (oxygen).
- Iron acts as the anode because it loses electrons and undergoes oxidation, while oxygen acts as the cathode because it gains electrons and undergoes reduction.
- This process of electron transfer between the anode and cathode forms an electrochemical cell, known as a galvanic cell.

b) Electrons flow from anode to cathode through the metal while ions flow through the water droplets:
- As mentioned earlier, iron acts as the anode where it loses electrons. These electrons flow through the metal from the anode to the cathode, which is oxygen.
- On the other hand, during the corrosion process, water droplets (moisture) present on the iron surface serve as an electrolyte.
- The moisture dissociates into ions, and these ions flow through the water droplets, completing the circuit in the electrochemical cell.

c) Dissolved O2 oxidizes Fe2+ to Fe3+ before it is deposited as rust (Fe2O3.H2O):
- When iron reacts with oxygen, it forms various iron oxides, including Fe2O3.H2O, commonly known as rust.
- In the presence of dissolved oxygen (O2), iron atoms on the iron surface are oxidized from Fe2+ to Fe3+ ions.
- These Fe3+ ions then combine with hydroxide ions (OH-) from the water droplets to form rust, Fe2O3.H2O.

d) All the above are observed:
- All the statements mentioned in options (a), (b), and (c) are correct and observed during the corrosion of iron.
- The formation of an electrochemical cell, flow of electrons through the metal, flow of ions through water droplets, and oxidation of Fe2+ to Fe3+ before rust formation are all part of the corrosion process.

Therefore, the correct answer is option 'D' as all the statements are true and observed during the corrosion of iron.
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Only One Option Correct TypeThis section contains 17multiple choice questions. Each question has four choices (a), (b), (c) and (d), out of which ONLY ONE is correctQ. In corrosion of irona)an electrochemical (galvanic cell) is formed in which Fe acts as anode and where O2is reduced, is the cathodeb)electrons flow from anode to cathode through the metal while ions flow through the water dropletsc)dissolved O2 oxidises Fe2+ to Fe3+ before itisdeposited as rust (Fe2O3.H2O)d)All the above are observedCorrect answer is option 'D'. Can you explain this answer?
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Only One Option Correct TypeThis section contains 17multiple choice questions. Each question has four choices (a), (b), (c) and (d), out of which ONLY ONE is correctQ. In corrosion of irona)an electrochemical (galvanic cell) is formed in which Fe acts as anode and where O2is reduced, is the cathodeb)electrons flow from anode to cathode through the metal while ions flow through the water dropletsc)dissolved O2 oxidises Fe2+ to Fe3+ before itisdeposited as rust (Fe2O3.H2O)d)All the above are observedCorrect answer is option 'D'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Only One Option Correct TypeThis section contains 17multiple choice questions. Each question has four choices (a), (b), (c) and (d), out of which ONLY ONE is correctQ. In corrosion of irona)an electrochemical (galvanic cell) is formed in which Fe acts as anode and where O2is reduced, is the cathodeb)electrons flow from anode to cathode through the metal while ions flow through the water dropletsc)dissolved O2 oxidises Fe2+ to Fe3+ before itisdeposited as rust (Fe2O3.H2O)d)All the above are observedCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Only One Option Correct TypeThis section contains 17multiple choice questions. Each question has four choices (a), (b), (c) and (d), out of which ONLY ONE is correctQ. In corrosion of irona)an electrochemical (galvanic cell) is formed in which Fe acts as anode and where O2is reduced, is the cathodeb)electrons flow from anode to cathode through the metal while ions flow through the water dropletsc)dissolved O2 oxidises Fe2+ to Fe3+ before itisdeposited as rust (Fe2O3.H2O)d)All the above are observedCorrect answer is option 'D'. Can you explain this answer?.
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