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प्रश्न
What is corrosion?
Give a brief account of corrosion.
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उत्तर
Corrosion is the damage caused to the metal by the chemical reaction of air, water, and acids with the surface of the metal. Generally, reactive metals corrode easily, and non-reactive metals have good resistance to corrosion.
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संबंधित प्रश्न
What is an alloy?
Which of the following methods is suitable for preventing an iron frying pan from rusting?
What is anodising? Give its applications.
What special name is given to the corrosion of iron?
What is meant by galvanisation? Why is it done?
In one method of rust prevention, the iron is not coated with anything. Which is this method?
The process of depositing a thin layer of zinc on iron articles is called ______.
Why is an iron grill painted frequently?
With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.
What are the constituents of stainless steel?
What are the special properties of stainless steel?
In stainless steel alloy, iron metal is mixed with ______.
Name the metal which is a constituent of blood pigment?
Name the metal which is a constituent of plant pigment?
What is corrosion? What are necessary conditions for corrosion?
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Write scientific reasons.
Lemon or tamarind is used for cleaning copper vessels turned greenish.
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 ..................................................................
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a) What is meant by corrosion?
b) Write names of any two methods of prevention of corrosion.
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d) Explain this method with diagram.
What is done to prevent corrosion of metals?
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Observe the following picture and answer the following questions:
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- Write the chemical formula of rust.
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- Write the reaction of oxidation of iron at the cathode.
- What is corrosion?
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Write scientific reason.
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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.
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Give preventive methods by giving examples of corrosion?
What is rust?
State two conditions necessary for rusting of iron.
Amalgam is an alloy of ____________.
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State whether the following statement is true or false:
Ships suffer a lot of damage though they are painted.
Give scientific reasons.
Silver amalgam is used for filling dental cavities.
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
