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प्रश्न
In the extraction of aluminium: Write the function and formula of cryolite in the extraction of aluminium.
In the extraction of aluminium Write the function and chemical formula of cryolite
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उत्तर
Cryolite is added to the molten mixture of alumina to reduce the melting point. The formula of cryolite is Na3AlF6.
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संबंधित प्रश्न
Which metal becomes black in the presence of hydrogen sulphide gas in air?
What is meant by the 'concentration of ore'?
How is sodium metal extracted? Explain with the help of equation of the reaction involved.
How is aluminium metal extracted? Explain with the help of an equation.
Name two ores of zinc. Write the names of the chemical compounds present in them and give their chemical formulae.
A metal which exists as a liquid at room temperature is obtained by heating its sulphide ore in the presence of air.
(a) Name the metal and write its chemical symbol.
(b) Write the name and formula of the sulphide ore.
(c) Give the equations of chemical reactions involved in the production of metal from its sulphide ore.
(d) Name a common device in which this metal is used.
(e) Can this metal displace copper from copper sulphate solution? Why?
Which metal can be extracted from the following ore?
bauxite
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write reaction for process?
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a) What is the atomic number of this element?
b) What is the group of this element?
c) To which period does this element belong?
Give the chemical formula of :
Cryolite
Name the following:
The substance added to get rid of gangue in the extraction of metal.
Compare the process of calcination and roasting.
Sulphide ores : Roasting : : Carbonate ores : _______
Zinc sulphide : Roasting : : zinc carbonate : _______
Identify who I am!
Ore of Aluminum- ______
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Ferric oxide is reacted with aluminium.
2 mL each of concentrated HCl, HNO3 and a mixture of concentrated HCl and concentrated HNO3 in the ratio of 3 : 1 were taken in test tubes labelled as A, B and C. A small piece of metal was put in each test tube. No change occurred in test tubes A and B but the metal got dissolved in test tube C respectively. The metal could be
On the basis of reactivity metals are grouped into three categories:
- Metals of low reactivity
- Metals of medium reactivity
- Metals of high reactivity
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Metals of high reactivity are extracted from their ores by electrolysis of the molten ore.
Metals of low reactivity are extracted from their sulphide ores, which are converted into their oxides. The oxides of these metals are reduced to metals by simple heating.
(a) Name the process of reduction used for a metal that gives vigorous reaction with air and water both.
(b) Carbon cannot be used as a reducing agent to obtain aluminium from its oxide? Why?
(c) Describe briefly the method to obtain mercury from cinnabar. Write the chemical equation for the reactions involved in the process.
OR
(c) Differentiate between roasting and calcination giving chemical equation for each.
