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प्रश्न
In Electrolytic reduction of alumina, Anode : _______ : : Cathode : Graphite lining
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उत्तर
In Electrolytic reduction of alumina, Anode : Set of carbon (graphite) rods : : Cathode : Graphite lining
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संबंधित प्रश्न
Which metal becomes black in the presence of hydrogen sulphide gas in air?
Name two metals which are always found in combined state.
An ore of manganese metal is:
(a) bauxite
(b) haematite
(c) cuprite
(d) pyrolusite
Which of the following is an iron ore?
(a) cinnabar
(b) calamine
(c) haematite
(d) rock salt
The metal which is always present in an amalgam is:
(a) iron
(b) aluminium
(c) mercury
(d) magnesium
Calamine ore can be converted into zinc oxide by the process of:
(a) dehydration
(b) roasting
(c) calcination
(d) sulphonation
Give the chemical formula of :
Bauxite
Name the following:
The substance added to get rid of gangue in the extraction of metal.
What is meant by concentration of ores?
The following questions relate to the extraction of aluminium by electrolysis.
Explain why it is necessary to renew the anode periodically.
X is an element in the form of a powder. X burns in oxygen and the product is soluble in water. The solution is tested with litmus. Write down only the word which will correctly complete each of the following sentences:
(a) If X is a metal, then the litmus will turn ______.
(b) If X is a non-metal, then the litmus will turn ______.
(c) If X is a reactive metal, then ______ will be evolved, when X reacts with dilute sulphuric acid.
(d) If X is a non -metal, it will form _ oxide, which will form ______ solution with water.
(e) If X is a non -metal, it will not conduct electricity unless it is carbon in the form of ______.
To protect iron from rusting, it is coated with a thin layer of zinc. Name the process.
Define calcination.
What is the difference between calcination and roasting?
Find the odd one out and give its explanation.
Explain Bayer’s process of concentration of bauxite with a chemical equation.
Oxides of moderately reactive metals like Zinc, Iron, Nickel, Tin, Copper, etc. are reduced by using:
Electrical wires have a coating of an insulting material. The material, generally used is
On the basis of reactivity metals are grouped into three categories:
- Metals of low reactivity
- Metals of medium reactivity
- Metals of high reactivity
Therefore metals are extracted in pure form from their ores on the basis of their chemical properties.
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.
