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प्रश्न
Name the following: Main ore of aluminium.
उत्तर
Bauxite (Al2O3.nH2O) is the main ore of aluminium.
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संबंधित प्रश्न
In the extraction of aluminium: Name the process of concentration of bauxite.
Give reasons.
Carbonate and sulphide ores are usually converted into oxides during the process of extraction.
Which metal becomes black in the presence of hydrogen sulphide gas in air?
Name one metal which is extracted by reduction with carbon.
Fill in the following blank with suitable word:
The rocky material found with ores is called.............
Which one of the methods given in column I is applied for the extraction of each of the metals given in column II:
| Column I | Column II |
| Electrolytic reduction | Aluminium |
| Reduction with Carbon | Zinc |
| Reduction with Aluminium | Sodium |
| Iron | |
| Manganese | |
| Tin |
Explain giving one example, how highly reactive metals (which are high up in the reactivity series) are extracted.
Explain why, an aqueous solution of sodium chloride is not used for the electrolytic extraction of sodium metal.
Name the metal which is extracted from haematite ore.
Name the electrode at which aluminium metal is produced.
The two metals which can be extracted just by heating their sulphides in air are:
(a) sodium and copper
(b) copper and aluminium
(c) potassium and zinc
(d) mercury and copper
An important ore of zinc metal is:
(a) calamine
(b) cuprite
(c) pyrolusite
(d) haematite
The major ore of aluminium is known as:
(a) cinnabar
(b) calamine
(c) bauxite
(d) pyrolusite
The two metals which are extracted by means of electrolytic reduction of their molten salts are:
(a) magnesium and manganese
(b) iron and aluminium
(c) zinc and magnesium
(d) magnesium and aluminium
Calamine ore can be used to extract one of the following metals. This metal is:
(a) copper
(b) mercury
(c) aluminium
(d) zinc
The metal which is always present in an amalgam is:
(a) iron
(b) aluminium
(c) mercury
(d) magnesium
The metal which can be extracted from pyrolusite ore is:
(a) mercury
(b) manganese
(c) aluminium
(d) magnesium
State three objectives achieved during the roasting of ores.
Give the principles of the hydrolytic method.
State why aluminium is extracted from its oxide by electrolysis while copper, lead, iron by reducing agents and mercury and silver by thermal decomposition.
Give reasons, why aluminum is used in:
painting electric and telegraphic poles
Aluminum is used in thermite welding:
what is thermit?
Identify the process given in following passage and draw neat labelled diagram showing the process.
Electrolysis of molten mixture of alumina (melting point > 20000C) is done in a steel tank. The tank has a graphite lining on the inner side. This lining does the work of a cathode. A set of graphite rods dipped in the molten electrolyte works as anode. Cryolite (Na3AlF6) and fluorspar (CaF2) are added in the mixture to lower its melting point upto 10000C.
Give the chemical formula of :
Cryolite
Name the following:
The substance added to get rid of gangue in the extraction of metal.
Define the term : Gangue
Define the term : Slag
Which method of refining is used to get 99.8% pure aluminium?
Write equations for each of the above metal which reacts with water.
Complete the incomplete statement with missing word:
Metals form positive ions while non- metals ______.
Sulphide ores : Roasting : : Carbonate ores : _______
Write the name.
The process of strong heating of carbonate ores in insufficient air–
Bauxite reacts with sodium hydroxide in the Bayer’s process.
Explain the reactions of nonmetals with water with the help of examples.
Explain the following reaction with the balanced equation.
Sodium aluminate reacts with water
Explain the following reaction with the balanced equation.
Zinc sulphide is heated strongly in excess of air
Which of the statements about the reaction, \[\ce{ZnO + CO -> Zn + CO2}\] is correct?
Iqbal treated a lustrous, divalent element M with sodium hydroxide. He observed the formation of bubbles in reaction mixture. He made the same observations when this element was treated with hydrochloric acid. Suggest how can he identify the produced gas. Write chemical equations for both the reactions.
During extraction of metals, electolytic refining is used to obtain pure metals.
(a) Which material will be used as anode and cathode for refining of silver metal by this process?
(b) Suggest a suitable electrolyte also.
(c) In this electrolytic cell, where do we get pure silver after passing electric current?
