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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.
संबंधित प्रश्न
M is a metal above hydrogen in the activity series and its oxide has the formula M2O. This oxide when dissolved in water forms the corresponding hydroxide which is a good conductor of electricity. In the above context, answer the following:
1) What kind of combination exists between M and O?
2)How many electrons are there in the outermost shell of M?
3) Name the group to which M belongs.
4) State the reaction taking place at the cathode.
5) Name the product at the anode.
In the extraction of aluminium: Draw the diagram for the extraction of aluminium.
Write the composition of the alloy called bronze.
Why do gold ornaments look new even after several years of use?
Name one metal which is extracted by reduction with aluminium.
Why does aluminium not corrode right through?
A zinc ore on heating in air forms sulphur dioxide. Describe briefly any two stages involved in the conversion of this concentrated ore into zinc metal.
How are the less reactive metals (which are quite low in the reactivity series) extracted? Explain with the help of an example.
Name the chemical compound which is electrolysed in molten state to obtain sodium metal. Which gas is produced in this process?
How is aluminium metal extracted? Explain with the help of an equation.
Aluminum is used in thermite welding:
what is thermit?
Define the following term.
Gangue
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
Name the electrode, from which aluminium collected.
Name the following:
Name two metals always find in combined state.
Complete the incomplete statement with missing word:
Metals are malleable while non-metals are ______.
Heating an ore in a limited supply of air or in the absence of air at a temperature just below its melting point is known as ______.
Observe the given figure of reactivity series of metals and answer the following questions:
Reactivity series of metals
- Name two metals which react with water.
- Name two moderately reactive metals.
- Name the most highly reactive metal and the most less reactive metal.
Write the name.
The process of extraction of aluminium from alumina-
Which of the following ore is concentrated by the Froth floatation process?
Iqbal treated a lustrous, divalent element M with sodium hydroxide. He observed the formation of bubbles in reaction mixture. He made the same observations when this element was treated with hydrochloric acid. Suggest how can he identify the produced gas. Write chemical equations for both the reactions.
