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प्रश्न
Stainless steel is an alloy of _______.
विकल्प
copper
tin
zinc
iron
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उत्तर
Stainless steel is an alloy of iron.
APPEARS IN
संबंधित प्रश्न
Which metals do not corrode easily?
Two methods by which rusting of iron can be prevented are ______ and ______.
Explain why Iron sheets are coated with zinc during galvanization.
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 ______.
______ 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 is the corrosion of iron known as?
No chemical reaction takes place when granules of a rusty-brown 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.
- What could the solids A and B be?
- What are the products C and D most likely to be?
- Write the chemical equation for the reaction between A and B leading to the formation of C and D. Mention the physical states of all the reactants and products in this equation and indicate the heat change which takes place.
- What is the special name of such a reaction? State one use of such a reaction.
- Name any two types of chemical reactions under which the above reaction can be classified.
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
State under what conditions corrosion is faster ?
Identify the process shown in the diagram and explain it in short
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.
Find the odd man out:
What is ‘rusting’?
Give reason.
An iron article should be given a coat of paint
Give reason.
A wooden article should be polished.
_______ is an alloy made from iron, carbon and chromium.
Corrosion of silver causes a black layer of _______.
_______ 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.
Write scientific reason.
Coins are made from metals and alloys.
Explain concept with example/explain with the help of a balanced equation.
Corrosion
Observe the following diagram and write answers.
- Name the method.
- Explain the method.
- Give two examples of this method.
Give preventive methods by giving examples of corrosion?
Give the equation for the formation of rust.
Amalgam is an alloy of ____________.
Copper objects lose their shine and form green coating of ____________.
Which among the following alloys contain mercury as one of its constituents?
The diagram shows the reaction between metal and dil. acid.
What is the reason for different behaviour of Mg in test tube B?
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?
| 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.
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
