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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
What chemical process is used for obtaining a metal from its oxide?
Name the following:
The property possessed by metals by which they can be beaten into sheets.
In the extraction of aluminium: Draw the diagram for the extraction of aluminium.
How many carats is pure gold? Why is pure gold not suitable for making ornaments?
Name the gas in air which tarnishes silver articles slowly.
Why does a new aluminium vessel lose shine so soon after use?
A zinc ore on heating in air forms sulphur dioxide. Describe briefly any two stages involved in the conversion of this concentrated ore into zinc metal.
Describe with one example, how moderately reactive metals (which are in the middle of reactivity series) are extracted.
What is meant by the 'concentration of ore'?
Name one ore of aluminium. Name the aluminium compound present in this ore and write its chemical formula.
Which of the following pair of metals exists in their native state in nature?
(a) Ag and Hg
(b) Ag and Zn
(c) Au and Hg
(d) Au and Ag
The metal which can be extracted simply by heating the cinnabar ore in air is:
(a) Zn
(b) Cu
(c) Al
(d) Hg
Rock salt is an ore of one of the following metals. This metal is:
(a) Mn
(b) Na
(c) Fe
(d) Cu
Zinc blende ore can be converted into zinc oxide by the process of:
(a) roasting
(b) hydrogenation
(c) chlorination
(d) calcination
Which metal can be extracted from the following ore?
bauxite
Give the principles of the froth floatation process.
State why aluminium is extracted from its oxide by electrolysis while copper, lead, iron by reducing agents and mercury and silver by thermal decomposition.
Name the anode, the cathode and the electrolyte used in the electrolytic refining of impure copper.
Give the chemical formula of :
Cryolite
Complete the incomplete statement with missing word:
Metals are malleable while non-metals are ______.
Complete the incomplete statement with missing word:
Metals form positive ions while non- metals ______.
Complete the incomplete statement with missing word:
Non-metals form acidic oxides while metals form ______.
Name a non- metal that has a metallic luster and sublimes on heating.
Which one of the following is not true of metal :
Metals form non-polar covalent compounds
Froth floatation process is generally used to concentrate ______ ores.
How is the method of extraction of metals high up in the reactivity series different from that for metals in the middle? Why can the same process not be applied for them? Name the process used for the extraction of these metals.
Sulphide ores : Roasting : : Carbonate ores : _______
Find the odd one out and give its explanation.
Write the name.
The molecular formula of main ore of aluminium –
Write the name.
The process of extraction of aluminium from alumina-
The electrolysis of alumina involves the use of fluorspar and cryolite to increase the melting point.
Write the molecular formulae of the following compound.
Fluorspar
Explain concept with example/explain with the help of a balanced equation.
Calcination
Observe the following diagram and write answers.
- Name the method.
- Write anode reaction and cathode reaction.
- Why fluorspar and cryolite are added in the mixture?
Explain in brief types of extraction of moderately reactive metals according to their reactivity.
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?
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.
