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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
Why do we apply paint on iron articles?
Which of the following methods is suitable for preventing an iron frying pan from rusting?
What special name is given to the corrosion of iron?
The chemical reaction involved in the corrosion of iron metal is that of ______.
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?
Why is an iron grill painted frequently?
Name any two metals which do not corrode easily.
What is the corrosion of iron known as?
With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.
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?
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.
- Name the metals X and Y.
- Which of the two metals is more reactive: X or Y?
- Name one ore or metal X. Also write its chemical formula.
- Name one ore of metal Y. Also write its chemical formula.
- 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?
Mention two uses of the following metals and non-metals
Iron
Name the metal which is a constituent of plant pigment?
What is corrosion? What are necessary conditions for corrosion?
Compare roasting and calcination.
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?
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.
_______ forms a green colour in the water.
Stainless steel is an alloy of _______.
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 |
Explain concept with example/explain with the help of a balanced equation.
Corrosion
Draw a neat labelled diagram.
Electrolysis
Write a molecular formula for rust.
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?
The process of coating the surface of the metal with a thin layer of zinc is called ______
What is rust?
Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of ____________.
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:
Alloys are homogeneous mixtures of a metal with a metal or non-metal. Which among the following alloys contain non-metal as one of its constituents?
State whether the following statement is true or false:
Ships suffer a lot of damage though they are painted.
Give an example of a chemical reaction for the following situation:
Sound is produced
