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प्रश्न
Explain in brief types of extraction of highly reactive metals according to their reactivity.
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उत्तर
Extraction of highly reactive metals:
- Highly reactive metals such as sodium, magnesium and calcium are obtained by electrolytic reduction.
- The metals are deposited at the cathode (negatively charged electrode), whereas chlorine gas is liberated at the anode (positively charged electrode).
E.g. For extraction of sodium metal, cathode and anode reactions are as follows:
At cathode: \[\ce{Na+ + e^- -> Na}\] (Reduction)
At anode: \[\ce{2Cl- -> Cl2 + 2e^-}\] (Oxidation)
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संबंधित प्रश्न
In the extraction of aluminium: Name the process of concentration of bauxite.
Name the following:
The property possessed by metals by which they can be beaten into sheets.
Name the method by which aluminium metal is extracted.
Define the term mineral.
Explain why, an aqueous solution of sodium chloride is not used for the electrolytic extraction of sodium metal.
Calamine ore can be used to extract one of the following metals. This metal is:
Rock salt is an ore of one of the following metals. This metal is:
Give reasons, why aluminum is used in:
In making ships
Name the following:
Name two metals always find in combined state.
Name:
The allotrope of the non-metal carbon which conducts electricity.
Name a non- metal that has a metallic luster and sublimes on heating.
Name the following:
A compound which is added to lower the fusion temperature of the electrolytic bath in the extraction of aluminium.
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.
In Electrolytic reduction of alumina, Anode : _______ : : Cathode : Graphite lining
Write the name.
Metals which are amphoteric in nature.
Explain the concept of Calcination.
Which of the following ore is concentrated by the Froth floatation process?
- Given below are the steps for extraction of copper from its ore. Write the reaction involved.
- Roasting of copper (I) sulphide
- Reduction of copper (I) oxide with copper (I) sulphide.
- Electrolytic refining
- Draw a neat and well labelled diagram for electrolytic refining of copper
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.
The given reaction shows one of the processes to extract the metals like Iron and Manganese.
\[\ce{MnO2(s) + Al(s) -> Mn(l) + Al2O3(s) + Heat}\]
Give a reason why Aluminium is preferably used in thermite reactions.
