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प्रश्न
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
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उत्तर
Aluminium and zinc are two metals that resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface. Aluminium and zinc form tough layers of aluminium oxide and zinc oxide by reacting with air.
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संबंधित प्रश्न
Give two examples of alloys with their chemical composition.
Two methods by which rusting of iron can be prevented are ______ and ______.
Explain why Iron sheets are coated with zinc during galvanization.
What is meant by galvanisation? Why is it done?
Explain why, iron sheets are coated with zinc.
In one method of rust prevention, the iron is not coated with anything. Which is this method?
Fill in the following blanks with suitable words:
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Fill in the following blank with suitable word:
The corrosion of copper produces a .............. coating of basic copper carbonate on its surface
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Name five methods of preventing rusting of iron.
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Explain how the activity series accounts for each of the following:
tendency to corrosion
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
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.
Observe the following picture a write down the chemical reaction with the explanation.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Give a reason why rust turns moist red litmus blue.
To prevent corrosion of iron and steel _______ method is used.
Which among the following alloys contain mercury as one of its constituents?
