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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?
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.
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संबंधित प्रश्न
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.
Name five methods of preventing rusting of iron.
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
State under what conditions corrosion is faster ?
Write a short note on Alloying.
Find the odd one out and give its explanation.
Explain concept with example/explain with the help of a balanced equation.
Corrosion
Give the equation for the formation of rust.
The table shown below gives information about four substances: A, B, C and D.
| SUBSTANCE | MELTING POINT (K) | ELECTRICAL CONDUCTIVITY | |
| SOLID | LIQUID/ AQUEOUS | ||
| A | 295 | Good | Good |
| B | 1210 | Poor | Good |
| C | 1890 | Poor | Good |
| D | 1160 | Poor | Poor |
Identify Ionic compounds from the above given substances.
| A process of forming a thick oxide of aluminium when aluminium is exposed to air. This coat makes it resistant to corrosion. Resistance can be improved by making a layer of oxide thinker. In this technique, the aluminium article is the anode, and the electrolyte is sulphuric acid. The anode reaction results in the formation of a black-coloured film of aluminium oxide on the anode. By putting appropriate dyes in the electrolytic solution, both coloured surface with the decorative finish is achieved. Kitchen articles like anodised such as pressure cookers, pans and frames of sliding windows are applications of this technique. |
- Name the anode and electrolyte used in this technique.
- How can we make aluminium articles made resistant to corrosion?
- Name the technique used to coat the aluminium articles.
