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प्रश्न
What is corrosion?
Give a brief account of corrosion.
What is meant by corrosion?
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उत्तर
Corrosion is the damage caused to the metal by the chemical reaction of air, water, and acids with the surface of the metal. Generally, reactive metals corrode easily, and non-reactive metals have good resistance to corrosion.
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संबंधित प्रश्न
What is an alloy?
Write two methods of preventing the rusting of iron.
Give reasons:
Platinum, gold and silver are used to make jewellery.
Two methods by which rusting of iron can be prevented are ______ and ______.
What is anodising? Give its applications.
Explain the term “corrosion” with an example. Write a chemical equation to show the process of corrosion of iron.
What type of chemical reaction is involved in the corrosion of iron?
The chemical reaction involved in the corrosion of iron metal is that of ______.
Name the metal which is used for galvanising iron.
State two conditions for the rusting of iron.
The corrosion of iron is called ______.
The process of depositing a thin layer of zinc on iron articles is called ______.
Tiffin boxes are electroplated with ______ but car bumpers are electroplated with ______ to protect them from rusting.
The corrosion of copper produces a ______ coating of basic copper carbonate on its surface.
______ 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.
Name any two metals which do not corrode easily.
Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
In stainless steel alloy, iron metal is mixed with ______.
Mention two uses of the following metals and non-metals
Iron
Bronze is an alloy of ______.
Name the metal which is a constituent of blood pigment?
Name the metal which is a constituent of plant pigment?
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.
Write scientific reasons.
Lemon or tamarind is used for cleaning copper vessels turned greenish.
Identify the process shown in the diagram and explain it in short
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Write three methods of preventing rusting of iron.
Give reason.
An iron article should be given a coat of paint
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.
Graphite is a lustrous non-metal which conducts electricity.
Write a short note on Alloying.
Pressure cooker : Anodizing : : Silver plated spoons : _______
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write the name.
An alloy of copper and tin-
Write the name.
Method used to present corrosion of copper.
Write scientific reason.
Coins are made from metals and alloys.
Draw a neat labelled diagram.
Electrolysis
Draw a neat labelled diagram.
Anodizing
Observe the following diagram and write answers.
- Name the method.
- Explain the method.
- Give two examples of this method.
Give solutions by giving examples of corrosion?
State two conditions necessary for rusting of iron.
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.
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:
Identify the correct statement from the following:
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?
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?
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?
Give an example of a chemical reaction for the following situation:
Sound is produced
