Question

16. This question concerns aluminium and some of its compounds a. Describe the amphoteric nature of aluminium oxide. Use equations to support your answer. (3) b. Explain the following statements: i. Aluminium saucepans can not be washed using caustic soda. (1) ii. When aqueous sodium hydroxide is added to a solution of an aluminium salt a white precipitate is formed which dissolves in excess sodium hydroxide solution. (2) iii. Aluminium carbonate can not be prepared by precipitation reaction. Support your answer by an equation. (2) (Total:

Answer 1

Answer:

Aluminium oxide (IUPAC name) or aluminum oxide (American English) is a chemical compound of aluminium and oxygen with the chemical formula Al2O3. It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium(III) oxide. It is commonly called alumina and may also be called aloxide, aloxite, or alundum depending on particular forms or applications. It occurs naturally in its crystalline polymorphic phase α-Al2O3 as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire. Al2O3 is significant in its use to produce aluminium metal, as an abrasive owing to its hardness, and as a refractory material owing to its high melting point.