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प्रश्न
In ______ process a layer of molten tin is deposited on metals.
पर्याय
Anodization
Tinning
Galvanizing
Alloying
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उत्तर
In tinning process a layer of molten tin is deposited on metals.
Explanation:
A greenish layer forms on the surface of a copper or brass vessel. This greenish layer is poisonous. If buttermilk or curry is placed in such a vessel, it gets spoiled. Tinning is done to prevent all such damages.
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संबंधित प्रश्न
Give two examples of alloys with their chemical composition.
Tinning : Tin : : Galvanizing : _________
Write two methods of preventing the rusting of iron.
What are alloys?
Two methods by which rusting of iron can be prevented are ______ and ______.
What type of chemical reaction is involved in the corrosion of iron?
Name the metal which is used for galvanising iron.
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?
Why is an iron grill painted frequently?
Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
In stainless steel alloy, iron metal is mixed with ______.
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 ______.
Compare roasting and calcination.
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.
Give reason.
An iron article should be given a coat of paint
Give a reason why rust turns moist red litmus blue.
State whether the statement given below is true or false. If false write the correct statement.
Either oxygen or moisture is essential 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?
_______ is an alloy made from iron, carbon and chromium.
Which of the following method is used to prevent the accumulation of greenish layer on brass due to corrosion?
Corrosion of silver causes a black layer of _______.
_______ forms a green colour in the water.
Stainless steel is an alloy of _______.
Rusting of iron : Fe2O3 : : corrosion of copper : ______
Find the odd one out and give its explanation.
Write scientific reason.
On exposure to air, silver articles turn blackish after some time.
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 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.
The process of coating the surface of the metal with a thin layer of zinc is called ______
What is rust?
Give the equation for the formation of rust.
A man painted his main gate made up of iron, to
- prevent it from rusting.
- protect it from sun.
- make it look beautiful.
- make it dust free.
Which of the above statement(s) is/are correct?
Galvanisation is a process used to prevent the rusting of which of the following?
Explain the chemical reactions in rusting of iron.
| 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.
