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प्रश्न
Which of the following method is used to prevent the accumulation of greenish layer on brass due to corrosion?
विकल्प
electroplating
anodization
tinning
alloying
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उत्तर
tinning
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संबंधित प्रश्न
Give two examples of alloys with their chemical composition.
Write two methods of preventing the rusting of iron.
Explain the terms Corrosion
Explain why rusting of iron objects is faster in coastal areas than in deserts.
Write a chemical equation to show the process of corrosion of iron.
Why is an iron grill painted frequently?
What is corrosion?
What is meant by 'rusting of iron'? With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.
What are the special properties of stainless steel?
Name an alloy of copper. State its chemical composition and any one use.
Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
A common metal which is highly resistant to corrosion is:
(a) iron
(b) copper
(c) aluminium
(d) magnesium
No chemical reaction takes place when granules of a rusty-brown 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.
(a) What could the solids A and B be?
(b) What are the products C and D most likely to be?
(c) Write the chemical equation for the reaction between A and B leading to the formation of C and D. Mention the physical states of all the reactants and products in this equation and indicate the heat change which takes place.
(d) What is the special name of such a reaction? State one use of such a reaction.
(e) Name any two types of chemical reactions under which the above reaction can be classified.
Mention two uses of the following metals and non-metals
Iron
Explain how the activity series accounts for each of the following:
tendency to corrosion
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.
Find the odd man out:
What are the adverse effects of corrosion?
Choose the correct alternative and rewrite the following:
Iron is _____________________.
Give reason.
An iron article should be given a coat of paint
Give reason for the following:
A suspension of rust is basic in nature.
When one of the metals in an alloy is mercury the alloy is called _______.
Bronze : _______ : : Stainless steel : Fe + Cr + C
Match the columns.
| Group A | Group B |
| 1) Electroplating | a) Pressure cooker |
| 2) Anodising | b) Silver plated spoons |
| c) Coating of tin on copper | |
| d) Coating of Zinc on iron |
Write scientific reason.
Anodization method is useful for prevention of the corrosion of the aluminium.
Give preventive methods by giving examples of corrosion?
The process of coating the surface of the metal with a thin layer of zinc is called ______
Amalgam is an alloy of ____________.
Copper objects lose their shine and form green coating of ____________.
Which among the following alloys contain mercury as one of its constituents?
Alloys are homogeneous mixtures of a metal with a metal or nonmetal. Which among the following alloys contain non-metal as one of its constituents?
A man painted his main gate made up of iron, to
- prevent it from rusting.
- protect it from sun.
- make it look beautiful.
- make it dust free.
Which of the above statement(s) is/are correct?
Iron pillar near the Qutub Minar in Delhi is famous for the following facts. Which of these facts is responsible for its long stability?
Galvanisation is a process used to prevent the rusting of which of the following?
Gold plated ornaments is the example of ______.
Explain the chemical reactions in rusting of iron.
In ______ process a layer of molten tin is deposited on metals.
