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प्रश्न
Write the molecular formulae of the following compound.
Cryolite
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उत्तर
Cryolite- Na3AlF6
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संबंधित प्रश्न
Write the steps involved in the extraction of pure metals in the middle of the activity series from their carbonate ores.
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Explain giving equation, what happens when:
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Gangue
Give the chemical formula of :
Cryolite
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Explain why it is necessary to renew the anode periodically.
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Metal will have 1 or 2 or 3 electrons in their valence shell.
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Explain in brief types of extraction of less reactive metals according to their reactivity.
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?
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- What is gangue?
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