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प्रश्न
Write the name.
Metals which are amphoteric in nature.
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उत्तर
Metals which are amphoteric in nature- Aluminium (Al), zinc (Zn)
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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.
Write the steps involved in the extraction of pure metals in the middle of the activity series from their carbonate ores.
In the extraction of aluminium: Write the function and formula of cryolite in the extraction of aluminium.
Name one metal which is extracted by reduction with carbon.
Name one metal which is extracted by reduction with aluminium.
Name the gas produced when calamine ore is calcined.
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 iron ore?
(a) cinnabar
(b) calamine
(c) haematite
(d) rock salt
Rock salt is an ore of one of the following metals. This metal is:
(a) Mn
(b) Na
(c) Fe
(d) Cu
In an electrolytic tank, aluminium metal is being extracted by the electrolysis of molten aluminium oxide using carbon electrodes. It is observed that one of the carbon electrodes is gradually burnt away and has to be replaced.
(a) Which carbon electrode (cathode or anode) is burnt away?
(b) Why is this carbon electrode burnt away?
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 following:
A compound which is added to lower the fusion temperature of the electrolytic bath in the extraction of aluminium.
Which one of the following is not true of metal :
Metals are good conductors of electricity.
choose the most appropriate term to match the given description.
Heating of the ore in the absence of air to high temperature
In Electrolytic reduction of alumina, Anode : _______ : : Cathode : Graphite lining
Bauxite reacts with sodium hydroxide in the Bayer’s process.
Write the molecular formulae of the following compound.
Fluorspar
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 statements about the reaction, \[\ce{ZnO + CO -> Zn + CO2}\] is correct?
