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प्रश्न
Name the following:
Main ore of aluminium.
Name the ore for aluminium.
Give one word for the following:
An ore of aluminium.
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उत्तर
Bauxite (Al2O3.nH2O) is the main ore of aluminium.
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संबंधित प्रश्न
Define the Ore.
How is copper extracted from its sulphide ore? Explain the various steps supported by chemical equations. Draw labelled diagram for the electrolytic refining of copper.
Name one metal which is extracted by:
Reduction with carbon.
How is manganese extracted from manganese dioxide, MnO2? Explain with the help of an equation.
Define the term mineral.
Name three other metals which are extracted in a manner similar to sodium.
How is aluminium metal extracted? Explain with the help of an equation.
Name two ores of zinc. Write the names of the chemical compounds present in them and give their chemical formulae.
Which of the following is an ore of mercury metal?
Which of the following reactants are used to carry out the thermite reaction required for welding the broken railway tracks?
A black metal oxide XO2 is used as a catalyst in the preparation of oxygen gas from potassium chlorate. The oxide XO2 is also used in ordinary dry cells. The metal oxide XO2 cannot be reduced satisfactorily with carbon to form metal X.
- Name the metal X.
- Name the metal oxide XO2.
- Which reducing agent can be used to reduce XO2 to obtain metal X?
- Name another metal which can also be extracted by the reduction of its oxide with the above reducing agent.
State three objectives achieved during the roasting of ores.
Give the principles of electromagnetic separation.
Some metallic oxides can be reduced by hydrogen, carbon and carbon monoxide and some cannot. Explain.
Give reasons, why aluminum is used in:
In making ships
Define the following term.
Mineral
State one observation for each of the following :
Copper sulphate solution is electrolysed using copper electrodes.
Name the following:
Two metals which are found in the free or native state.
Name the following:
The mixture of materials fed into a furnace to extract a metal.
Name the following:
The substance added to get rid of gangue in the extraction of metal.
What is meant by concentration of ores?
Name the methods by which concentrated ore is converted to metallic oxide.
Froth floatation process is generally used to concentrate ______ ores.
Extraction of moderately reactive elements is done by _______ and _______ method.
Sulphide ores : Roasting : : Carbonate ores : _______
The electrolysis of alumina involves the use of fluorspar and cryolite to increase the melting point.
Write the molecular formulae of the following compound.
Sodium aluminate
Explain the following reaction with the balanced equation.
Zinc carbonate is heated strongly in limited supply of air
Explain concept with example/explain with the help of a balanced equation.
Roasting
Explain in brief types of extraction of moderately reactive metals according to their reactivity.
Observe the figure and answer the following.
- Write the name of the method.
- What is used as anode and cathode in this method?
- Write the molecular formula and use of cryolite.
- Write anode reaction.
- Write cathode reaction.
Answer the questions on the following passage.
The minerals from which the metal can be separated economically are called ores. Ores contain many types of impurities such as soil, sand and rocky substances along with metal compounds. These impurities are called gangue.
Metals can be extracted from their ores by means of various methods of separation. The process of extraction of metal in a pure state from the ores is also a part of metallurgy.
Ores are taken out from the mines and the gangue is usually separated from the ore at the site itself by various methods. Then the ores are carried out to the place where metals are produced. Here metals are extracted in pure form. Then metals are further purified by different methods of purification. This entire process is called metallurgy. Most metals being reactive do not occur in nature in the free state but are found in combined state as their salts such as oxides, carbonates, sulphides, and nitrates. however, the most unreactive metals that are not affected by air, water and other natural factors like silver, gold, platinum, generally occur in a free state. The compounds of metals that occur in nature along with the impurities are called minerals.
- What are ores?
- Which processes are involved in the branch of metallurgy? What is metallurgy?
- Which metals are found in a free state?
- In what forms are metals found in combined state?
- What is gangue?
The process in which a carbonate ore is heated strongly in the absence of air to convert it into metal oxide is called ____________.
Which of the statements about the reaction, \[\ce{ZnO + CO -> Zn + CO2}\] is correct?
On the basis of reactivity metals are grouped into three categories:
- Metals of low reactivity
- Metals of medium reactivity
- Metals of high reactivity
Therefore metals are extracted in pure form from their ores on the basis of their chemical properties.
Metals of high reactivity are extracted from their ores by electrolysis of the molten ore.
Metals of low reactivity are extracted from their sulphide ores, which are converted into their oxides. The oxides of these metals are reduced to metals by simple heating.
(a) Name the process of reduction used for a metal that gives vigorous reaction with air and water both.
(b) Carbon cannot be used as a reducing agent to obtain aluminium from its oxide? Why?
(c) Describe briefly the method to obtain mercury from cinnabar. Write the chemical equation for the reactions involved in the process.
OR
(c) Differentiate between roasting and calcination giving chemical equation for each.
The given reaction shows one of the processes to extract the metals like Iron and Manganese.
\[\ce{MnO2(s) + Al(s) -> Mn(l) + Al2O3(s) + Heat}\]
Identify the substance oxidised and reduced in the above reaction.
Assertion (A): The extraction of metals from their sulphide ores cannot take place without roasting the ore.
Reason (R): Roasting converts sulphide ores directly into metals.
