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प्रश्न
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?
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उत्तर
- The given diagram represents anodizing process used for the prevention of corrosion.
- This method is used for the prevent corrosion of aluminium and copper.
- In this method, copper or aluminium article is used as the anode.
APPEARS IN
संबंधित प्रश्न
Explain how painting of an iron gate prevents it from rusting.
Explain why Iron sheets are coated with zinc during galvanization.
What is anodising? Give its applications.
Explain the term “corrosion” with an example. Write a chemical equation to show the process of corrosion of iron.
What special name is given to the corrosion of iron?
The chemical reaction involved in the corrosion of iron metal is that of ______.
Explain why, iron sheets are coated with zinc.
In one method of rust prevention, the iron is not coated with anything. Which is this method?
Tiffin boxes are electroplated with ______ but car bumpers are electroplated with ______ to protect them from rusting.
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
Name five methods of preventing rusting of iron.
What are the constituents of stainless steel?
A common metal which is highly resistant to corrosion is ______.
Mention two uses of the following metals and non-metals
Iron
Name the metal which is a constituent of plant pigment?
Explain how the activity series accounts for each of the following:
tendency to corrosion
What is corrosion? What are necessary conditions for corrosion?
Corrosion can be an advantage in some case.Explain ?
Answer the following question.
a) What is meant by corrosion?
b) Write names of any two methods of prevention of corrosion.
c) In which method, metal like copper, aluminium are coated with a thin layer of their oxides by means of electrolysis.
d) Explain this method with diagram.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Answer the following question.
List two properties of alloys.
Give reason.
An iron article should be given a coat of paint
Give reason.
Copper and brass utensils should be tinned.
Explain the term – rusting and give a word equation for the formation of rust. If polished iron nails are kept in three separate test tubes, state the contents in each test tube required, to prove the conditions for rusting.
Observe the following picture and answer the following questions:
- What is rust?
- Write the chemical formula of rust.
- Write the reaction of oxidation of iron at the anode.
- Write the reaction of oxidation of iron at the cathode.
- What is corrosion?
To prevent corrosion of iron and steel _______ method is used.
_______ forms a green colour in the water.
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.
On exposure to air, silver articles turn blackish after some time.
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.
- Write the reactions on anode and cathode.
Which among the following alloys contain mercury as one of its constituents?
Galvanisation is a process used to prevent the rusting of which of the following?
Explain the following:
Lime water turns milky on passing carbon dioxide gas into it.
Give an example of a chemical reaction for the following situation:
Sound is produced
| 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.
