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प्रश्न
Name five methods of preventing rusting of iron.
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उत्तर
Five methods of preventing rusting of iron are:
- By polishing the surface of iron with paint
- By applying oil or grease on the surface of iron
- By coating a thin layer of zinc on the iron metal by the process called galvanisation
- By coating other metals like tin coating and chromium coating
- By alloying with other metals (chromium and nickel) to form stainless steel, which does not corrode
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संबंधित प्रश्न
What is an alloy?
Explain how painting of an iron gate prevents it from rusting.
What special name is given to the corrosion of iron?
Fill in the following blank with suitable word:
The corrosion of iron is called ................
Fill in the following blank with suitable word:
The corrosion of copper produces a .............. coating of basic copper carbonate on its surface
What is the corrosion of iron known as?
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Name an alloy of copper. State its chemical composition and any one use.
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No chemical reaction takes place when granules of a solid, A, are mixed with the powder of another solid, B. However when the mixture is heated, a reaction takes place between its components. One of the products, C, is a metal and settles down in the molten state while the other product, D, floats over it. It was observed that the reaction is highly exothermic.
(i) Based on the given information make an assumption about A and B and write a chemical equation for the chemical reaction indicating the conditions of reaction, physical state of reactants and products and thermal status of reaction.
(ii) Mention any two types of reactions under which above chemical reaction can be classified.
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Answer the following question.
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b) Write names of any two methods of prevention of corrosion.
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d) Explain this method with diagram.
Rusting of iron : Fe2O3 : : corrosion of copper : ______
Find the odd one out and give its explanation.
Draw a neat labelled diagram.
Anodizing
Write a molecular formula for rust.
Give the equation for the formation of rust.
The diagram shows the reaction between metal and dil. acid.
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Galvanisation is a process used to prevent the rusting of which of the following?
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
