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प्रश्न
Draw a well-labelled diagram of extraction of Aluminium. Write the anode reaction in electrolytic reduction of Alumina.
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उत्तर
At anode: \[\ce{2O^{2-} -> O2 + 4e-}\]
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संबंधित प्रश्न
Name one metal which is extracted by reduction with aluminium.
Explain how, mercury is extracted from its sulphide ore (cinnabar). Give equations of the reactions involved.
An important ore of zinc metal is:
(a) calamine
(b) cuprite
(c) pyrolusite
(d) haematite
Calamine ore can be used to extract one of the following metals. This metal is:
(a) copper
(b) mercury
(c) aluminium
(d) zinc
A sulphide ore is converted into metal oxide by the process of:
(a) carbonation
(b) roasting
(c) calcination
(d) anodising
State why aluminium is extracted from its oxide by electrolysis while copper, lead, iron by reducing agents and mercury and silver by thermal decomposition.
Explain the following:
Galvanization protects iron from rusting.
Complete the following by selecting the correct option from the choices given:
The metal which does not react with water or dilute H2SO4 but reacts with concentrated H2SO4 is _________
Define roasting.
How is the method of extraction of metals high up in the reactivity series different from that for metals in the middle? Why can the same process not be applied for them? Name the process used for the extraction of these metals.
Atomic number of aluminium is _______ and its electronic configuration is _______.
_______ is the least reactive metal.
Find the odd one out and give its explanation.
The electrolysis of alumina involves the use of fluorspar and cryolite to increase the melting point.
Explain Bayer’s process.
Explain concept with example/explain with the help of a balanced equation.
Ionic bond and ionic compounds
In thermite welding a mixture of ____________ is ignited with a burning magnesium ribbon which produces molten iron metal as a large amount of heat is evolved.
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.
Assertion (A): The extraction of metals from their sulphide ores cannot take place without roasting the ore.
Reason (R): Roasting converts sulphide ores directly into metals.
A mineral from which the metal can be extracted economically and conveniently is known as ______.
