Q7 of 11 Page 108

Explain the process of producing alumina from bauxite.

Bauxite is mixed with hot concentrated NaOH solution to dissolve aluminium oxide in it to produce sodium aluminate solution. This is filtered to remove impurities. This is diluted with water after adding a little Al(OH)3 to precipitate Al(OH)3. This precipitate is separated, washed well and strongly heated to remove water and obtain alumina.

The process is represented with the help of flowchart –



More from this chapter

All 11 →
5

How is iron extracted?

 6

Write the uses of the following:

• Pig iron


• Cast iron


• Alnico

 8

Explain the method of obtaining pure aluminium from alumina by electrolysis. In this process the carbon rods are replaced from time to time. Why?

 9

Explain what is anode mud.