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प्रश्न
State two conditions necessary for rusting of iron.
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उत्तर
- The presence of water and oxygen is essential for the rusting of iron.
- Impurities in the iron, the presence of the water vapor, acids, salts and carbon dioxide hastens rusting.
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संबंधित प्रश्न
What are alloys?
Explain how painting of an iron gate prevents it from rusting.
Name any three objects (or structures) which are gradually damaged by the corrosion of iron and steel.
Explain why, iron sheets are coated with zinc.
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
What are the constituents of stainless steel?
Four metals P, Q, R and S are all obtained by the reduction of their oxides with carbon. Metal P is used to form a thin layer over the sheets of metal S to prevent its corrosion. Metal Q is used for electroplating tiffin boxes made of metal S whereas metal R is used in making car batteries. Metals Q and R form an alloy called solder. What are metals P, Q, R and S? How have you arrived at this conclusion?
Answer the following question.
a) What is meant by corrosion?
b) Write names of any two methods of prevention of corrosion.
c) In which method, metal like copper, aluminium are coated with a thin layer of their oxides by means of electrolysis.
d) Explain this method with diagram.
State whether the statement given below is true or false. If false write the correct statement.
Either oxygen or moisture is essential for rusting.
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