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प्रश्न
What is an alloy?
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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.
Explain why rusting of iron objects is faster in coastal areas than in deserts.
Explain the term “corrosion” with an example. Write a chemical equation to show the process of corrosion of iron.
The chemical reaction involved in the corrosion of iron metal is that of ______.
Name the metal which is a constituent of plant pigment?
Explain how the activity series accounts for each of the following:
tendency to corrosion
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.
Write three methods of preventing rusting of iron.
Give reason.
A wooden article should be polished.
Observe the following picture and answer the following questions:
- What is rust?
- Write the chemical formula of rust.
- Write the reaction of oxidation of iron at the anode.
- Write the reaction of oxidation of iron at the cathode.
- What is corrosion?
When one of the metals in an alloy is mercury the alloy is called _______.
Rusting of iron : Fe2O3 : : corrosion of copper : ______
Bronze : _______ : : Stainless steel : Fe + Cr + C
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 |
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?
Explain the following:
Lime water turns milky on passing carbon dioxide gas into it.
Explain the following:
Bubbles are produced when acetic acid is added to a solution of sodium hydrogencarbonate.
Describe two changes that are harmful. Explain why you consider them harmful. How can you prevent them?
