What is the role of molten cryolite in the extraction of aluminium?

What is the role of molten cryolite in the extraction of aluminium?
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Answer :

When pure alumina is mixed with molten cryolite, it forms an electrolyte at 1223K. Molten cryolite also acts as a solvent for alumina.
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Related questions

Briefly explain the extraction of aluminium from alumina with chemical equations.

Description : Briefly explain the extraction of aluminium from alumina with chemical equations.

Last Answer : Aluminium oxide dissolved in molten cryolite is taken in a chamber with gently sloped base.The inner wall is made of carbon lining. Graphite rods are introduced in the electrolyte bath. The carbon lining ... is passed. Molten aluminium collects at the lining and flows out of the gently sloped base.

Why is pure alumina needed for the extraction of aluminium?

Description : Why is pure alumina needed for the extraction of aluminium?

Last Answer : For electrolysis of we need pure alumina. Hence bauxite is converted into alumina by chemical process.

Why is extraction of aluminium not commercially viable by using reducing agents like coke? OR Coke is used in the extraction of iron but not in the extraction of aluminium. Why? OR Aluminium cannot be extracted by heating bauxite and coke. Why?

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Last Answer : Oxygen of aluminium oxide cannot be easily taken away by reducing agents like coke.

What is cryolite? Write its chemical formula.

Description : What is cryolite? Write its chemical formula.

Last Answer : Cryolite is chemically sodium aluminium fluoride. Its molecular formula is Na3AlF6.

What is the role of coke in the extraction of iron?

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Last Answer : Coke is a good reducing agent. It reduces iron oxide to iron. It is also a good fuel which supplies heat energy for the chemical reactions.

State the role of lime stone in the extraction of iron from haematite. Or Why is lime stone added during the extraction of iron?

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Last Answer : Limestone reacts with the sand present as impurity in the ore forming calcium silicate which is taken out of the blast furnace as slag.

Why is slag collected above molten iron?

Description : Why is slag collected above molten iron?

Last Answer : Slag is lighter than molten iron and collects above molten iron. Slag prevents oxidations of molten iron back into iron oxide.

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Last Answer : Ans:(d)

Identify the correct statement with reference to the extractive metallurgy of aluminium. (A) The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3 (B) Approximately 80% of the aluminium deposited on the cathode comes from cryolite (C) Sodium is deposited along with aluminium, but is immediately vaporised (D) Anode effect sets in when the cryolite concentration goes below 40%.

Description : Identify the correct statement with reference to the extractive metallurgy of aluminium. (A) The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3 (B) Approximately 80% of ... is immediately vaporised (D) Anode effect sets in when the cryolite concentration goes below 40%.

Last Answer : (A) The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3

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Last Answer : The mixture of haematite, lime stone and coke is called charge.

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What happens when? a) A cleaned iron plate or iron nail is kept in 10g of copper sulphate solution. b) A pinch of mercuric oxide is kept in a test tube. c)A small crystal of silver nitrate is dissolved in distilled water and a drop of ammonium hydroxide & a pinch of glucose powder are added.

Description : What happens when? a) A cleaned iron plate or iron nail is kept in 10g of copper sulphate solution. b) A pinch of mercuric oxide is kept in a test tube. c)A small crystal of silver nitrate is dissolved in distilled water and a drop of ammonium hydroxide & a pinch of glucose powder are added.

Last Answer : a) A cleaned iron plate or iron nail is kept in 10g of copper sulphate solution. After a few hours a coating of copper is seen on iron nail/plate. It is based on displacement reaction. ... on the inner walls of the test tube. Aldehyde group in glucose reduced silver nitrate to metallic silver.

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Last Answer : a) Gangue The unwanted impurities present in the ore are called gangue. b) Concentration of ore The process of removing the gangue particles to increase the percentage of desired component of the ore ... flux. f) Slag The substance formed by the combination of impurities like sand is called slag.

Define metallurgy.

Description : Define metallurgy.

Last Answer : The technology of extraction of metals from their ores and refining them to required form is called metallurgy.

Give reason: Gold occurs in native form.

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Last Answer : Gold is low in the reactivity series. It is least reactive or unreactive. Hence gold is found in free state.