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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
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?
A zinc ore gave CO2 on treatment with a dilute acid. Identify the ore and write its chemical formula.
Write the composition of the alloy called bronze.
Which one of the methods given in column I is applied for the extraction of each of the metals given in column II:
| Column I | Column II |
| Electrolytic reduction | Aluminium |
| Reduction with Carbon | Zinc |
| Reduction with Aluminium | Sodium |
| Iron | |
| Manganese | |
| Tin |
Name the chemical compound which is electrolysed in molten state to obtain aluminium metal. Which gas is evolved during this process?
Name the chemical compound which is electrolysed in molten state to obtain sodium metal. Which gas is produced in this process?
What iron compound is present in haematite ore? Also write its chemical formula.
Name one ore of mercury. Which mercury compound is present in this ore? Write its chemical formula.
Calamine ore can be used to extract one of the following metals. This metal is:
Calamine ore can be converted into zinc oxide by the process of ______.
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.
- What are A and B?
- Identify C and D.
- What will be the action of C on litmus solution? Why?
- State whether element B is a solid, liquid or gas at room temperature.
- Write formula of the compound formed when element B reacts with an element E having atomic number 5.
Give the chemical formula of :
Sodium aluminate
The following question relate to the extraction of aluminium by electrolysis.
Give the equation for the reaction which takes place at the cathode.
To protect iron from rusting, it is coated with a thin layer of zinc. Name the process.
Which one of the following is not true of metal :
Metals form non-polar covalent compounds
Aluminium oxide is _______ oxide.
Extraction of moderately reactive elements is done by _______ and _______ method.
In Electrolytic reduction of alumina, Anode : _______ : : Cathode : Graphite lining
Explain the characteristics of ionic compounds.
Observe the following diagram and write answers.
- Name the method.
- Write anode reaction and cathode reaction.
- Why fluorspar and cryolite are added in the mixture?
