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Question
Three experiments to study the process of rusting are given below. Observe the three test tubes and answer the following questions.
- Why the nail in the test tube 2 is not rusted?
- Why is the nail in the test tube 1 is rusted highly?
- Would the nail in the test tube 3 get rusted?
Solution
Essential requirements for corrosion are:
- Supply of oxygen
- Presence of water
- Material itself
- The nail in test tube 2 is not rusted because, in test tube 2, we take boiling water. So, all the dissolved oxygen is removed from the water and if the iron nail does not get a supply of oxygen then corrosion is not carried out.
- The nail in test tube 1 is rusted highly because, in test tube 1, the iron nail meets all the requirements that are essential for the corrosion process. That's Supply of oxygen is dissolved form, presence of water and material itself.
- The nail in test tube 3 is not rusted because calcium chloride is one of the best absorbents. So, it absorbs all the dissolved oxygen present in water. Hence, the corrosion process does not take place.
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