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प्रश्न
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
What is the function of cryolite used along with alumina as the electrolyte?
उत्तर
In the extraction of aluminium, the metal is to be isolated from alumina (Al2O3) by carrying out its electrolytic reduction. The melting point of alumina veery high (2323K).
- It is therefore, mixed will cryolite ( Na2AlF6 ) which lowers its melting point to 1173 k.
- More over, cryolite also increase the electrical conductivity of alumina.
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संबंधित प्रश्न
Give reasons.
Carbonate and sulphide ores are usually converted into oxides during the process of extraction.
Why does a new aluminium vessel lose shine so soon after use?
Describe with one example, how moderately reactive metals (which are in the middle of reactivity series) are extracted.
Name the chemical compound which is electrolysed in molten state to obtain aluminium metal. Which gas is evolved during this process?
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
Why is powdered coke sprinkled on top of the electrolyte?
Name the following:
Two metals which are found in the free or native state.
Name:
The allotrope of the non-metal carbon which conducts electricity.
Define calcination.
Usually ______ ores are subjected to ______ which is done in the absence of air.
Write the name.
Metals which are amphoteric in nature.
