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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?
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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.
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संबंधित प्रश्न
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The property possessed by metals by which they can be beaten into sheets.
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How is manganese extracted from manganese dioxide, MnO2? Explain with the help of an equation.
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| Column I | Column II |
| Electrolytic reduction | Aluminium |
| Reduction with Carbon | Zinc |
| Reduction with Aluminium | Sodium |
| Iron | |
| Manganese | |
| Tin |
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How is aluminium metal extracted? Explain with the help of an equation.
Name the following:
Two metals which are found in the free or native state.
Define the term:
Slag
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Metals form positive ions while non- metals ______.
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Metals form non-polar covalent compounds
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