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प्रश्न
Bronze is an alloy of ______.
पर्याय
copper and tin
copper and zinc
tin and zinc
copper, zinc and tin
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उत्तर
Bronze is an alloy of copper and tin.
Explanation:
Bronze is a solid alloy composed primarily of 88% copper and 12% tin. It is used in the production of hardware, utensils musical instruments, medals, and other items. Due to its resistance to corrosion caused by seawater, it is used in submerged bearings and ship propellants.
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संबंधित प्रश्न
What is an alloy?
Why do we apply paint on iron articles?
Answer the following question.
What are alloys?
Which of the following methods is suitable for preventing an iron frying pan from rusting?
Two methods by which rusting of iron can be prevented are ______ and ______.
Name any three objects (or structures) which are gradually damaged by the corrosion of iron and steel.
The chemical reaction involved in the corrosion of iron metal is that of:
(a) oxidation as well as displacement
(b) reduction as well as combination
(c) oxidation as well as combination
(d) reduction as well as displacement
In one method of rust prevention, the iron is not coated with anything. Which is this method?
Fill in the following blank with suitable word:
The process of depositing a thin layer of zinc on iron articles is called .............
Fill in the following blank with suitable word:
The corrosion of copper produces a .............. coating of basic copper carbonate on its surface
Explain why, through aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.
What is corrosion?
Name any two metals which do not corrode easily.
Give the constituents and one use of brass.
What are the constituents of stainless steel?
Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
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.
(a) What could the solids A and B be?
(b) What are the products C and D most likely to be?
(c) 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.
(d) What is the special name of such a reaction? State one use of such a reaction.
(e) 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?
State under what conditions corrosion is faster ?
Compare roasting and calcination.
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
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 ..................................................................
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 are the adverse effects of corrosion?
Write three methods of preventing rusting of iron.
What is "rusting"? Describe with a labelled diagram an activity to investigate the conditions under which iron rusts.
Give reason.
An iron article should be given a coat of paint
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.
Pressure cooker : Anodizing : : Silver plated spoons : _______
Bronze : _______ : : Stainless steel : Fe + Cr + C
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write scientific reason.
Anodization method is useful for prevention of the corrosion of the aluminium.
Draw a neat labelled diagram.
Electroplating
Draw a neat labelled diagram.
Anodizing
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?
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?
What is rust?
Give the equation for the formation of rust.
Which among the following alloys contain mercury as one of its constituents?
Alloys are homogeneous mixtures of a metal with a metal or nonmetal. Which among the following alloys contain non-metal as one of its constituents?
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?
State whether the following statement is true or false:
Ships suffer a lot of damage though they are painted.
Explain the following:
Lime water turns milky on passing carbon dioxide gas into it.
Explain the following:
Bubbles are produced when acetic acid is added to a solution of sodium hydrogencarbonate.
Gold plated ornaments is the example of ______.
