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प्रश्न
In one method of rust prevention, the iron is not coated with anything. Which is this method?
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उत्तर
Alloying of iron with chromium and nickel to produce stainless steel (that does not corrode) is one method where iron is not coated with anything.
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संबंधित प्रश्न
What is an alloy?
Give two examples of alloys with their chemical composition.
Write two methods of preventing the rusting of iron.
Choose the correct answer from the options given below:
Heating an ore in a limited supply of air or in the absence of air at a temperature just below its melting point is known as
A. Smelting
B. Ore-dressing
C. Calcination
D. Bessemerisation
Name the metal which is used for galvanising iron.
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.
If copper is kept exposed to damp air for a considerable time, it gets a green coating on its surface. This is due to the formation of:
(a) hydrated copper sulphate
(b) copper oxide
(c) basic copper carbonate
(d) copper nitrate
Name the metal which is a constituent of plant pigment?
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.
Give reason for the following:
A suspension of rust is basic in nature.
Find the odd one out and give its explanation.
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 |
Explain concept with example/explain with the help of a balanced equation.
Corrosion
Observe the following figure and write the answer of the question.
- Which process is shown in the figure?
- Explain the chemical reaction shown in the figure.
- Write the reactions on anode and cathode.
State two conditions necessary for rusting of iron.
Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of ____________.
Marble’s popularity began in ancient Rome and Greece, where white and off-white marble were used to construct a variety of structures, from hand-held sculptures to massive pillars and buildings.
The substance not likely to contain CaCO3 is:
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?
In ______ process a layer of molten tin is deposited on metals.
