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प्रश्न
Pressure cooker : Anodizing : : Silver plated spoons : _______
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उत्तर
Pressure cooker : Anodizing : : Silver plated spoons : Electroplating
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संबंधित प्रश्न
Write two methods of preventing the rusting of iron.
Which of the following methods is suitable for preventing an iron frying pan from rusting?
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.
What is meant by galvanisation? Why is it done?
Fill in the following blanks with suitable words:
Tiffin boxes are electroplated with .............. but car bumpers are electroplated with ............... to protect them from rusting.
What is the corrosion of iron known as?
A common metal which is highly resistant to corrosion is:
(a) iron
(b) copper
(c) aluminium
(d) magnesium
Four metals P, Q, R and S are all obtained by the reduction of their oxides with carbon. Metal P is used to form a thin layer over the sheets of metal S to prevent its corrosion. Metal Q is used for electroplating tiffin boxes made of metal S whereas metal R is used in making car batteries. Metals Q and R form an alloy called solder. What are metals P, Q, R and S? How have you arrived at this conclusion?
Explain how the activity series accounts for each of the following:
tendency to corrosion
Corrosion can be an advantage in some case.Explain ?
Complete the process of iron rusting by filling the blanks. Suggest a way to prohibit the process.
The iron rust is formed due to........................... reaction. Different
regions on iron surface become anode and cathode.
Reaction on anode region :
`F_e(s) → Fe^(2+) (aq) +2e^-`
Reaction on anode region :
`O_2(g) + 4H^+(aq) +............................ → 2H_2 O (l) `
When Fe2+ ions migrate from anode region they react with ................... to form Fe3+ ions.
A reddish coloured hydrated oxide is formed from ............... ions. It is called rust.
`2Fe_(3+) (aq) + 4H_2O(l) → ................. + 6H_+(aq) `
A way to prevent rusting ..................................................................
Identify the process shown in the diagram and explain it in short

Find the odd man out:
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
What is ‘rusting’?
Give reason.
An iron article should be given a coat of paint
Give reason.
A wooden article should be polished.
Give reason.
Copper and brass utensils should be tinned.
Give a reason why rust turns moist red litmus blue.
Give reason for the following:
A suspension of rust is basic in nature.
Which of the following method is used to prevent the accumulation of greenish layer on brass due to corrosion?
To prevent corrosion of iron and steel _______ method is used.
When one of the metals in an alloy is mercury the alloy is called _______.
Bronze : _______ : : Stainless steel : Fe + Cr + C
Find the odd one out and give its explanation.
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 |
Write scientific reason.
Coins are made from metals and alloys.
Draw a neat labelled diagram.
Anodizing
Write a molecular formula for rust.
Observe the following diagram and give answers.

- Name this method of prevention of corrosion.
- For prevention of which metal this method is used?
- What is used as anode in this method?
What is rust?
Copper objects lose their shine and form green coating of ____________.
Generally, when metals are treated with mineral acids, hydrogen gas is liberated but when metals (except Mn and Mg), treated with HNO3, hydrogen is not liberated, why?
Galvanisation is a process used to prevent the rusting of which of the following?
In ______ process a layer of molten tin is deposited on metals.
