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प्रश्न
Write scientific reason.
Anodization method is useful for prevention of the corrosion of the aluminium.
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उत्तर
- The process of coating metals such as aluminium and copper with a thin and strong layer of their oxides by electrolysis is called anodizing process.
- When aluminium is anodized, a thin layer of aluminium oxide is formed all over the surface. This restricts the contact of aluminium metal with oxygen and water and prevents corrosion of aluminium.
Hence, anodization method is useful for prevention of the corrosion of the aluminium.
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संबंधित प्रश्न
What is an alloy?
Explain the term corrosion.
Which metals do not corrode easily?
Which of the following methods is suitable for preventing an iron frying pan from rusting?
Explain why Iron sheets are coated with zinc during galvanization.
Explain the term “corrosion” with an example. Write a chemical equation to show the process of corrosion of iron.
Name any three objects (or structures) which are gradually damaged by the corrosion of iron and steel.
The chemical reaction involved in the corrosion of iron metal is that of ______.
State two conditions for the rusting of iron.
In one method of rust prevention, the iron is not coated with anything. Which is this method?
The corrosion of copper produces a ______ coating of basic copper carbonate on its surface.
What is corrosion?
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
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 ______.
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- 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.
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Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
Choose the correct alternative and rewrite the following:
Iron is _____________________.
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A wooden article should be polished.
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_______ forms a green colour in the water.
Pressure cooker : Anodizing : : Silver plated spoons : _______
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Find the odd one out and give its explanation.
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Electrolysis
Complete flow chart given below.
Observe the following diagram and give answers.
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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 |
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Explain the following:
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Give an example of a chemical reaction for the following situation:
Sound is produced
