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प्रश्न
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?
उत्तर
- The minerals from which the metal can be separated economically are called ores.
- The extraction of metals from their ores by various methods of separation and further purification to obtain pure metals are involved in the branch of metallurgy.
The extraction of metals from their ores and then refining them for use is known as metallurgy. - Metals such as silver, gold and platinum are found in free state.
- Metals are found in combined states as their salts such as oxides, carbonates, sulphides, and nitrates.
- The unwanted impurities of soil, sand, rocky substances, etc., present in the ore are called gangue.
संबंधित प्रश्न
Metallic oxides of zinc, magnesium and copper were heated with the following metals.
Metal | Zinc | Magnesium | Copper |
Zinc oxide | – | – | – |
Magnesium oxide | – | – | – |
Copper oxide | – | – | – |
In which cases will you find displacement reactions taking place?
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.
Silver metal does not combine easily with oxygen but silver jewellery tarnishes after some time. How?
Explain given equation, what happens when ZnCO3 is heated in the absence of air?
Explain how, mercury is extracted from its sulphide ore (cinnabar). Give equations of the reactions involved.
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
Rock salt is an ore of one of the following metals. This metal is:
(a) Mn
(b) Na
(c) Fe
(d) Cu
An element has its electron configuration as 2,8,8,2. Now answer the following questions.
a) What is the atomic number of this element?
b) What is the group of this element?
c) To which period does this element belong?
Define the following term.
Mineral
Name the following:
Two metals which are found in the free or native state.
Name the following:
The process in which an ore is heated in air so that oxygen gets added to it to form the oxides.
Complete the following by selecting the correct option from the choices given:
The metal which does not react with water or dilute H2SO4 but reacts with concentrated H2SO4 is _________
Name the methods by which concentrated ore is converted to metallic oxide.
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.
In electrolytic reduction of alumina _______ is used as a cathode.
In the electrolytic reduction of alumina, the lining of graphite acts as an anode.
Bauxite reacts with sodium hydroxide in the Bayer’s process.
Explain in brief types of extraction of highly reactive metals according to their reactivity.
The process in which a carbonate ore is heated strongly in the absence of air to convert it into metal oxide is called ____________.
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.