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प्रश्न
Explain how painting of an iron gate prevents it from rusting.
How does the painting of an iron object prevent its rusting?
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उत्तर १
Moisture (water) and air (oxygen) aid rusting. By painting an iron gate, we prevent its contact with the air and moisture present in the atmosphere.
उत्तर २
- The regular method used to prevent rusting of iron objects is painting the surfaces of iron objects. Rusting takes place in the presence of both air and water.
- Thus, when a layer of paint is applied to the surface of an iron object, it prevents the contact of air and moisture with the iron surface and avoids the rusting of iron objects.
संबंधित प्रश्न
Give two examples of alloys with their chemical composition.
Name the metal which is used for galvanising iron.
State two conditions for the rusting of iron.
Name any two metals which do not corrode easily.
Name five methods of preventing rusting of iron.
Name an alloy of copper. State its chemical composition and any one use.
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.
- What could the solids A and B be?
- What are the products C and D most likely to be?
- 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.
- What is the special name of such a reaction? State one use of such a reaction.
- Name any two types of chemical reactions under which the above reaction can be classified.
State under what conditions corrosion is faster ?
Which among the following alloys contain mercury as one of its constituents?
Give scientific reasons.
Silver amalgam is used for filling dental cavities.
