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प्रश्न
Write the name.
An alloy of copper and tin-
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उत्तर
An alloy of copper and tin- Bronze
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संबंधित प्रश्न
What is an alloy?
Name any three objects (or structures) which are gradually damaged by the corrosion of iron and steel.
Name the metal which is used for galvanising iron.
The process of depositing a thin layer of zinc on iron articles is called ______.
Tiffin boxes are electroplated with ______ but car bumpers are electroplated with ______ to protect them from rusting.
The corrosion of copper produces a ______ coating of basic copper carbonate on its surface.
______ and ______ are necessary for the rusting of iron.
Explain why, though aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.
What are the constituents of stainless steel?
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 ______.
Brass is an alloy of ______.
Explain how the activity series accounts for each of the following:
tendency to corrosion
Compare roasting and calcination.
No chemical reaction takes place when granules of a solid, A, are mixed with the powder of another solid, B. However when the mixture is heated, a reaction takes place between its components. One of the products, C, is a metal and settles down in the molten state while the other product, D, floats over it. It was observed that the reaction is highly exothermic.
(i) Based on the given information make an assumption about A and B and write a chemical equation for the chemical reaction indicating the conditions of reaction, physical state of reactants and products and thermal status of reaction.
(ii) Mention any two types of reactions under which above chemical reaction can be classified.
Observe the following picture a write down the chemical reaction with the explanation.
What are the adverse effects of corrosion?
Write three methods of preventing rusting of iron.
What is ‘rusting’?
Give reason.
Copper and brass utensils should be tinned.
Give reason for the following:
A suspension of rust is basic in nature.
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?
Stainless steel is an alloy of _______.
When one of the metals in an alloy is mercury the alloy is called _______.
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 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?
Give the equation for the formation of rust.
State two conditions necessary for rusting of iron.
Identify the correct statement from the following:
Gold plated ornaments is the example of ______.
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.
