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प्रश्न
Bronze is an alloy of ______.
पर्याय
copper and tin
copper and zinc
tin and zinc
copper, zinc and tin
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?
Give two examples of alloys with their chemical composition.
Write two methods of preventing the rusting of iron.
Explain the terms Corrosion
Which of the following methods is suitable for preventing an iron frying pan from rusting?
Write a chemical equation to show the process of corrosion of iron.
What special name is given to their corrosion of iron?
What is meant by galvanisation? Why is it done?
Explain why, iron sheets are coated with zinc.
Fill in the following blank with suitable word:
The process of depositing a thin layer of zinc on iron articles is called .............
Give the constituents and one use of brass.
What are the special properties of stainless steel?
Explain why, when a copper object remains in damp air for a considerable time, a green coating is formed on its surface. What is this process known as?
Brass is an alloy of:
(a) Cu and Sn
(b) Cu and Pb
(c) Pb and Sn
(d) Zn and Cu
A metal X which is resistant to corrosion is produced by the electrolysis of its molten oxide whereas another metal Y which is also resistant to corrosion is produced by the reduction of its oxide with carbon. Metal X can be used in powder form in thermite welding whereas metal Y is used in making cathodes of ordinary dry cells.
(a) Name the metals X and Y.
(b) Which of the two metals is more reactive : X or Y?
(c) Name one ore or metal X. Also write its chemical formula.
(d) Name one ore or metal Y. Also write its chemical formula.
(e) Name one alloy of metal X and one alloy of metal Y.
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 ?
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.
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 ..................................................................
Identify the process shown in the diagram and explain it in short
What is done to prevent corrosion of metals?
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.
Answer the following question.
List two properties of alloys.
Give reason.
An iron article should be given a coat of paint
Give reason.
A wooden article should be polished.
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.
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.
Graphite is a lustrous non-metal which conducts electricity.
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.
Corrosion of silver causes a black layer of _______.
To prevent corrosion of iron and steel _______ method is used.
When one of the metals in an alloy is mercury the alloy is called _______.
Pressure cooker : Anodizing : : Silver plated spoons : _______
Rusting of iron : Fe2O3 : : corrosion of copper : ______
Bronze : _______ : : Stainless steel : Fe + Cr + C
Find the odd one out and give its explanation.
Write scientific reason.
Anodization method is useful for prevention of the corrosion of the aluminium.
Write scientific reason.
Coins are made from metals and alloys.
Draw a neat labelled diagram.
Anodizing
What is rust?
Write a molecular formula for rust.
Give preventive methods by giving examples of corrosion?
What is rust?
Amalgam is an alloy of ____________.
Copper objects lose their shine and form green coating of ____________.
The diagram shows the reaction between metal and dil. acid.
What is the reason for different behaviour of Mg in test tube B?
Marble’s popularity began in ancient Rome and Greece, where white and off-white marble were used to construct a variety of structures, from hand-held sculptures to massive pillars and buildings.
The substance not likely to contain CaCO3 is:
A man painted his main gate made up of iron, to
- prevent it from rusting.
- protect it from the sun.
- make it look beautiful.
- make it dust-free.
Which of the above statement(s) is/are correct?
The iron pillar near the Qutub Minar in Delhi is famous for the following facts. Which of these facts is responsible for its long stability?
Galvanisation is a process used to prevent the rusting of which the following?
State whether the following statements are 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.
Gold plated ornaments is the example of ______.
Give scientific reasons.
Silver amalgam is used for filling dental cavities.
Explain the chemical reactions in rusting of iron.
In ______ process a layer of molten tin is deposited on metals.
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
