How can you separate alumina from silica | Class 12 Chemistry Chapter General Principles and Processes of Isolation of Elements, General Principles and Processes of Isolation of Elements NCERT Solutions

Q22.

How can you separate alumina from silica in bauxite ore associated with silica? Give equations, if any.

To separate alumina from silica in bauxite ore associated with silica, first the powdered ore is digested with a concentrated NaOH solution at 473 - 523 K and 35 - 36 bar pressure. This results in the leaching out of alumina (Al2O3) as sodium aluminate and silica (SiO2) as sodium silicate leaving the impurities behind.

Then, CO2 gas is passed through the resulting solution to neutralize the aluminate in the solution, which results in the precipitation of hydrated alumina. To induce precipitation, the solution is seeded with freshly prepared samples of hydrated alumina.

During this process, sodium silicate remains in the solution. The obtained hydrated alumina is filtered, dried, and heated to get back pure alumina.

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What is the correct answer to: How can you separate alumina from silica in bauxite ore associated with silica? Give equations, if any.?

To separate alumina from silica in bauxite ore associated with silica, first the powdered ore is digested with a concentrated NaOH solution at 473 - 523 K and 35 - 36 bar pressure. This results in the leaching out of alu...

How do you solve How can you separate alumina from silica in bauxite ore associated with silica? Give equations, if any. step by step?

Step-by-step explanation:
• To separate alumina from silica in bauxite ore associated with silica, first the powdered ore is digested with a concentrated NaOH solution at 473 - 523 K and 35 - 36 bar pressure
• This results in the leaching out of alumina (Al2O3) as sodium aluminate and silica (SiO2) as sodium silicate leaving the impurities behind


What common mistakes should be avoided in this question?

Students often lose marks by skipping steps, writing incomplete explanations, or misunderstanding keywords used in the question.

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Student Discussion

Naseema
Class · · , · Nov 01, 2019
So thankful
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Naseema
Class · · , · Nov 01, 2019
In second reaction the carbons and hydrogens are not balanced
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aayush
Class · · , · Feb 27, 2019
really helpful
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piyush
Class · · , · Feb 15, 2018
you are great
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