Why Doesn't Aluminium Corrode?

[Jadaav]

Hi guys,

I wanted to know why does Aluminium not corrode and why does it not form a carbonate when heat is applied to it?

 

[lightarrow]

It reacts immediately with air oxygen as soon as it comes in contact wit air, forming a very resistant and protective layer of aluminium oxide (corindone).

 

[Jadaav]

It reacts immediately with air oxygen as soon as it comes in contact wit air, forming a very resistant and protective layer of aluminium oxide (corindone).

Thanks:)

That means that the corindone protects the aluminium from corrosion.

And what about its reaction with heat to form carbonate? Does the corindone also protects it from heat or ?

 

[lightarrow]

Thanks:)

That means that the corindone protects the aluminium from corrosion.

And what about its reaction with heat to form carbonate? Does the corindone also protects it from heat or ?

What exactly do you mean with "reaction with heat"?

 

[Jadaav]

ah I meant when heat is applied to it

 

[Jadaav]

well, when I searched for corindone It lead me to corundum instead, guess its the same thing ?

'Aluminium oxide is the family of inorganic compounds with the chemical formula Al2O3. It is an amphoteric oxide and is commonly referred to as alumina, corundum as well as many other names, reflecting its widespread occurrence in nature and industry. Its most significant use is in the production of aluminium metal, although it is also used as an abrasive due to its hardness and as a refractory material due to its high melting point.'

This solves my questions about the corrosion and carbonate of Aluminium.

but still has a doubt of corindone and corundum, reply please

 

[lightarrow]

ah I meant when heat is applied to it

So you mean:

Al₂O₃ + 3CO₂ -->heat--> Al₂(CO₃)₃ ?

If you mean that reaction it's strange because usually carbonates decomposes, with heat. E.g. :

MgCO₃-->heat--> MgO + CO₂

Anyway, aluminium oxide doesn't react with CO2 essentially because it's extremely stable (inert) and also because it's not very basic (it's amphoteric).

 

[Jadaav]

So you mean:

Al₂O₃ + 3CO₂ -->heat--> Al₂(CO₃)₃ ?

If you mean that reaction it's strange because usually carbonates decomposes, with heat. E.g. :

MgCO₃-->heat--> MgO + CO₂

Anyway, aluminium oxide doesn't react with CO2 essentially because it's extremely stable (inert) and also because it's not very basic (it's amphoteric).

Why you react Aluminium oxide with Carbon dioxide?

 

[Jadaav]

I have now understood it completely:)

Aluminium oxide is a non-reactive gas and can only react as an acid or base.:)

that's going to help me very much for my exam:D

thanks very much mate;)

 

[lightarrow]

well, when I searched for corindone It lead me to corundum instead, guess its the same thing ?

Yes, forgive my mistake, I thought in english was the same as in italian...

 

[Borek]

I have now understood it completely:)

Aluminium oxide is a non-reactive gas and can only react as an acid or base.

If you are calling aluminum oxide a gas, you have still a lot to understand.

Note that corundum is a name for crystalline aluminum oxide. I doubt oxide layer on the metal surface is crystalline, microcrystalline at best.

 

[Jadaav]

Yes, forgive my mistake, I thought in english was the same as in italian...

Nevermind;),

Didn't expect to have this question in my exam, but glad that I could answer.

I didn't put aluminium oxide in the exam, hope fully.

It was only asked to explain briefly:D

 

[Jadaav]

If you are calling aluminum oxide a gas, you have still a lot to understand.

Note that corundum is a name for crystalline aluminum oxide. I doubt oxide layer on the metal surface is crystalline, microcrystalline at best.

I know, I'm still at a low level though.

 

[lightarrow]

Note that corundum is a name for crystalline aluminum oxide.

Correct.

I doubt oxide layer on the metal surface is crystalline, microcrystalline at best.

Yes, I agree with you.