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प्रश्न
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.
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उत्तर
(i) Solid A is assumed to be MnO2 and solid B to be Aluminium (Al).
When the mixture of MnO2 and Al is heated, manganese (Mn) is produced in molten state and aluminium oxide (Al2O3) floats over it. Mn is produced in the molten state as a lot of heat energy is released in the process.
The chemical equation for the reaction can be written as:
3MnO2(s) + 4Al(s) `triangle/`> 3Mn(f) + 2Al2O3(s) + Heat
(ii) The types of reaction under which the above reaction is classified are—
-
Redox reaction
-
Displacement reaction
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संबंधित प्रश्न
A common metal which is highly resistant to corrosion is:
(a) iron
(b) copper
(c) aluminium
(d) magnesium
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
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?
Find the odd one out and give its explanation.
Draw a neat labelled diagram.
Electroplating
Write a molecular formula for rust.
The diagram shows the reaction between metal and dil. acid.
What is the reason for different behaviour of Mg in test tube B?
Give an example of a chemical reaction for the following situation:
Sound is produced
Gold plated ornaments is the example of ______.
| A process of forming a thick oxide of aluminium when aluminium is exposed to air. This coat makes it resistant to corrosion. Resistance can be improved by making a layer of oxide thinker. In this technique, the aluminium article is the anode, and the electrolyte is sulphuric acid. The anode reaction results in the formation of a black-coloured film of aluminium oxide on the anode. By putting appropriate dyes in the electrolytic solution, both coloured surface with the decorative finish is achieved. Kitchen articles like anodised such as pressure cookers, pans and frames of sliding windows are applications of this technique. |
- Name the anode and electrolyte used in this technique.
- How can we make aluminium articles made resistant to corrosion?
- Name the technique used to coat the aluminium articles.
