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NTA Abhyas JEE Main2020Chemistryd and f Block ElementsPractice

Which of the following is not correct?

Options

  1. ARusting of iron can be stopped by increasing the concentration of C O 2 in water
  2. BRusting of iron is electrochemical in nature
  3. CRusting of iron takes place in moist air
  4. DRusting of iron produces hydrated iron (III) oxide

Correct answer

A. Rusting of iron can be stopped by increasing the concentration of C O 2 in water

Step-by-step solution

Rusting of iron is an electrochemical phenomenon in which one spot of iron acts as anode. F e s → F e 2 + a q + 2 e - These electrons move through the metal and are taken up by the oxygen already dissolved in water in presence of H + furnished by H 2 C O 3 , which is formed by the dissolution of C O 2 g in water. The concentration of H + depends upon the concentration of C O 2 in water. Cathode O 2 a q + 4 H + + 4 e - → 2 H 2 O l Since increase in the concentration of H + results in the increase in the rate of the

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