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प्रश्न
What is an alloy?
उत्तर
An alloy is a homogeneous mixture of two or more metals or of one or more metals with certain non-metallic elements.
संबंधित प्रश्न
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 how painting of an iron gate prevents it from rusting.
Explain why, iron sheets are coated with zinc.
Fill in the following blank with suitable word:
The corrosion of iron is called ................
Fill in the following blanks with suitable words:
............ and .............. are necessary for the rusting of iron.
What is corrosion?
Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.
A common metal which is highly resistant to corrosion is:
(a) iron
(b) copper
(c) aluminium
(d) magnesium
Explain how the activity series accounts for each of the following:
tendency to corrosion
State under what conditions corrosion is faster ?
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.
Write scientific reasons.
Lemon or tamarind is used for cleaning copper vessels turned greenish.
What are the adverse effects of corrosion?
Choose the correct alternative and rewrite the following:
Iron is _____________________.
Give reason.
An iron article should be given a coat of paint
Give a reason why rust turns moist red litmus blue.
Which of the following method is used to prevent the accumulation of greenish layer on brass due to corrosion?
Stainless steel is an alloy of _______.
Bronze : _______ : : Stainless steel : Fe + Cr + C
Write scientific reason.
Coins are made from metals and alloys.
Give preventive methods by giving examples of corrosion?
Amalgam is an alloy of ____________.
The iron pillar near the Qutub Minar in Delhi is famous for the following facts. Which of these facts is responsible for its long stability?
Explain the following:
Lime water turns milky on passing carbon dioxide gas into it.
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
