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प्रश्न
In the electrolytic method, a layer of highly active metal is applied to a less active metal.
पर्याय
Right
Wrong
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उत्तर
In the electrolytic method, a layer of highly active metal is applied to a less active metal- Wrong
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संबंधित प्रश्न
In the extraction of aluminium: Name the process of concentration of bauxite.
The process by which sulphide ore is concentrated.
Name one metal which is extracted by reduction with heat alone.
Name one ore of copper (other than cuprite). Which compound of copper is present in this ore? Also, write its chemical formula.
Name one ore of aluminium. Name the aluminium compound present in this ore and write its chemical formula.
How is aluminium metal extracted? Explain with the help of an equation.
The metal which can be extracted simply by heating the cinnabar ore in air is:
(a) Zn
(b) Cu
(c) Al
(d) Hg
Calamine ore can be converted into zinc oxide by the process of:
(a) dehydration
(b) roasting
(c) calcination
(d) sulphonation
An element A which is a part of common salt and kept under kerosene reacts with another element B of atomic number 17 to give a product C. When an aqueous solution of product C is electrolysed then a compound D is formed and two gases are liberated.
(a) What are A and B?
(b) Identify C and D.
(c) What will be the action of C on litmus solution? Why?
(d) Write formula of the compound formed when element B reacts with an element E having atomic number 5.
Which metal can be extracted from the following ore?
Haematite
Give the principles of the froth floatation process.
Give the principles of electromagnetic separation.
How an ore is concentrated by froth floatation process?
Which method of refining is used to get 99.8% pure aluminium?
Write the name.
The process of strong heating of carbonate ores in insufficient air–
Write the name.
The process of extraction of aluminium from alumina-
Explain the following reaction with the balanced equation.
Sodium aluminate reacts with water
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?
Explain the difference between Bayer’s process and Hall’s process by explaining the Bayer’s process.
Which of the following metals exist in their native state in nature?
(i) Cu
(ii) Au
(iii) Zn
(iv) Ag
