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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?
Give two examples of alloys with their chemical composition.
Write two methods of preventing the rusting of iron.
Two methods by which rusting of iron can be prevented are ______ and ______.
Explain why rusting of iron objects is faster in coastal areas than in deserts.
Choose the correct answer from the options given below:
Heating an ore in a limited supply of air or in the absence of air at a temperature just below its melting point is known as
A. Smelting
B. Ore-dressing
C. Calcination
D. Bessemerisation
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
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?
Explain why, through aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.
What is meant by 'rusting of iron'? With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.
Name an alloy of copper. State its chemical composition and any one use.
Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
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?
Name the metal which is a constituent of blood pigment?
Name the metal which is a constituent of plant pigment?
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 ..................................................................
Find the odd man out:
Choose the correct alternative and rewrite the following:
Iron is _____________________.
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
What is ‘rusting’?
Give reason.
An iron article should be given a coat of paint
Give reason.
Copper and brass utensils should be tinned.
Give a reason why rust turns moist red litmus blue.
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.
Write a short note on Alloying.
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 _______.
Pressure cooker : Anodizing : : Silver plated spoons : _______
Rusting of iron : Fe2O3 : : corrosion of copper : ______
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 the name.
Method used to prevent corrosion of copper.
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 the equation for the formation of rust.
Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of ____________.
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 table shown below gives information about four substances: A, B, C and D.
| SUBSTANCE | MELTING POINT (K) | ELECTRICAL CONDUCTIVITY | |
| SOLID | LIQUID/ AQUEOUS | ||
| A | 295 | Good | Good |
| B | 1210 | Poor | Good |
| C | 1890 | Poor | Good |
| D | 1160 | Poor | Poor |
Identify Ionic compounds from the above given substances.
Identify the correct statement from the following:
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?
Generally, when metals are treated with mineral acids, hydrogen gas is liberated but when metals (except Mn and Mg), treated with HNO3, hydrogen is not liberated, why?
Galvanisation is a process used to prevent the rusting of which of the following?
Give an example of a chemical reaction for the following situation:
Sound is produced
Explain the chemical reactions in rusting of iron.
