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प्रश्न
In the extraction of aluminium: Draw the diagram for the extraction of aluminium.
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उत्तर
Extraction of aluminium:
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संबंधित प्रश्न
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 |
How is zinc extracted from its carbonate or (calamine)? Explain with equations.
Define the terms gangue.
Name one ore of aluminium. Name the aluminium compound present in this ore and write its chemical formula.
During galvanisation, iron metal is given a thin coating of one of the following metals. This metal is:
(a) chromium
(b) tin
(c) zinc
(d) copper
The articles made of silver metal become dark on prolonged exposure to air. This is due to the formation of a layer of its:
(a) oxide
(b) hydride
(c) sulphide
(d) carbonate
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
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
What is the function of cryolite used along with alumina as the electrolyte?
Name the following:
The process in which an ore is heated in air so that oxygen gets added to it to form the oxides.
Name the following:
Name two metals always find in combined state.
Explain the following:
Galvanization protects iron from rusting.
What is passive iron?
To protect iron from rusting, it is coated with a thin layer of zinc. Name the process.
Which one of the following is not true of metal :
Metals form non-polar covalent compounds
Define roasting.
The electrolysis of alumina involves the use of fluorspar and cryolite to increase the melting point.
Explain concept with example/explain with the help of a balanced equation.
Ionic bond and ionic compounds
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?
Which of the following ore is concentrated by the Froth floatation process?
