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प्रश्न
Draw a well-labelled diagram of extraction of Aluminium. Write the anode reaction in electrolytic reduction of Alumina.
उत्तर
At anode: \[\ce{2O^{2-} -> O2 + 4e-}\]
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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: Why is it necessary to replace anodes time to time?
Which metal becomes black in the presence of hydrogen sulphide gas in air?
Fill in the following blank with suitable word:
Bronze is an alloy of copper and .........
Give the name and chemical formula of one ore of copper.
Explain givem equation, what happens when a mixture of Cu2O and Cu2S is heated?
Name two metals which are found in nature mainly in the free state (as metallic elements).
What iron compound is present in haematite ore? Also write its chemical formula.
Manganese metal is extracted from manganese dioxide by a reduction process by making use of:
(a) carbon
(b) hydrogen
(c) electrolysis
(d) aluminium
Zinc blende ore can be converted into zinc oxide by the process of:
(a) roasting
(b) hydrogenation
(c) chlorination
(d) calcination
Give the principles of electromagnetic separation.
Name the anode, the cathode and the electrolyte used in the electrolytic refining of impure copper.
Explain the following:
Galvanization protects iron from rusting.
Name : The metal which is liquid at room temperature.
Calcium, copper, lead, aluminium, zinc, chromium, magnesium, iron.
Choose the major metals from the list given above to make the following alloys:
(a) Stainless steel
(b) brass
choose the most appropriate term to match the given description.
Heating of the ore in the absence of air to high temperature
Froth floatation process is generally used to concentrate ______ ores.
Explain the following reaction with the balanced equation.
Ferric oxide is reacted with aluminium.
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?
Which of the following ore is concentrated by the Froth floatation process?
