Aluminium is mainly extracted by ……………………

Lead is mainly extracted by :

Correct the following statements by changing the underlined part of the sentence : Aluminium is mainly extracted from ul("corrundum")

Aluminium is extracted by dissolving aluminium oxide in ..

Correct the following statements by changing the underlined part of the sentence : Aluminium ul("can be") extracted by the electrolysis of an aqueous solution of an aluminium salt.

Explain why : Aluminium cannot be extracted by reducing alumina with carbon.

Aluminium is extracted from bauxite by the electrolysis of aluminium oxide dissolved in cryolite. Now answer the following question: Write the formula of cryolite.