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प्रश्न
Find the odd one out and give its explanation.
पर्याय
Tinning
Alloying
Anodization
Froth floatation
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उत्तर
Froth floatation
Explanation-
Froth floatation is a method used for the concentration of ores while others are methods used for the prevention of corrosion.
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संबंधित प्रश्न
Why do we apply paint on iron articles?
Which metals do not corrode easily?
Two methods by which rusting of iron can be prevented are ______ and ______.
Name the metal which is used for galvanising iron.
Tiffin boxes are electroplated with ______ but car bumpers are electroplated with ______ to protect them from rusting.
Give the constituents of brass.
Name a common metal which is highly resistant to corrosion.
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.
Bronze is an alloy of ______.
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.
Observe the following picture a write down the chemical reaction with the explanation.
Identify the process shown in the diagram and explain it in short
What is done to prevent corrosion of metals?
What are the adverse effects of corrosion?
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.
Corrosion of silver causes a black layer of _______.
_______ forms a green colour in the water.
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 |
The process of coating the surface of the metal with a thin layer of zinc is called ______
Give the equation for the formation of rust.
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?
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?
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
Gold plated ornaments is the example of ______.
