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प्रश्न
Find the odd one out and give its explanation.
विकल्प
Brass
Bronze
Phosphorous
Steel
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उत्तर
Phosphorous
Explanation-
Phosphorus is nonmetal while others are alloys.
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संबंधित प्रश्न
What is an alloy?
Give two examples of alloys with their chemical composition.
Give reasons:
Platinum, gold and silver are used to make jewellery.
Two methods by which rusting of iron can be prevented are ______ and ______.
Explain why Iron sheets are coated with zinc during galvanization.
What is anodising? Give its applications.
What type of chemical reaction is involved in the corrosion of iron?
Name the metal which is used for galvanising iron.
Explain why, iron sheets are coated with zinc.
The process of depositing a thin layer of zinc on iron articles is called ______.
Why is an iron grill painted frequently?
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 ______.
Name the metal which is a constituent of plant pigment?
Corrosion can be an advantage in some case.Explain ?
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.
Identify the process shown in the diagram and explain it in short
What is done to prevent corrosion of metals?
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
Give reason.
An iron article should be given a coat of paint
Give reason.
Copper and brass utensils should be tinned.
Pressure cooker : Anodizing : : Silver plated spoons : _______
Rusting of iron : Fe2O3 : : corrosion of copper : ______
Find the correlation:
Bronze : ______ :: Tin : Cu+Zn.
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 scientific reason.
Coins are made from metals and alloys.
Draw a neat labelled diagram.
Electrolysis
Draw a neat labelled diagram.
Anodizing
What is rust?
Observe the following figure and write the answer of the question.
- Which process is shown in the figure?
- Explain the chemical reaction shown in the figure.
- Write the reactions on anode and cathode.
Copper objects lose their shine and form green coating of ____________.
Identify the correct statement from the following:
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?
Iron pillar near the Qutub Minar in Delhi is famous for the following facts. Which of these facts is responsible for its long stability?
State whether the following statement is 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.
Explain the chemical reactions in rusting of iron.
