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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: kimi85 on July 22, 2007, 01:25:19 AM

Title: Why can't aluminum react with HNO3?
Post by: kimi85 on July 22, 2007, 01:25:19 AM

Why can't aluminum react with HNO₃?

Is it because aluminum can form hydrates? Thanks!

Title: Re: Aluminum
Post by: enahs on July 22, 2007, 11:26:55 AM

Aluminum is highly reactive with air. It forms a fairly chemically inert protective coating around the aluminum metal that is exposed to air. What is this coating and write the balanced chemical equations for Al + O2 -> ?.

Title: Re: Aluminum
Post by: kimi85 on July 22, 2007, 11:05:17 PM

4Al   +  3O2  --> 2Al₂O₃

Title: Re: Aluminum
Post by: kimi85 on July 22, 2007, 11:06:49 PM

thanks..so, aluminum oxide is the coating? and is the reason why aluminum cant react with nitric acid?

Title: Re: Why can't aluminum react with HNO3?
Post by: AWK on July 23, 2007, 02:21:15 AM

Aluminium reacts with diluted HNO3. When concentrated HNO3 is use passivation occurs, ie HNO3 oxidizes surface of Al to Al2O3 which in turn is insoluble in concentrated HNO3.

Title: Re: Why can't aluminum react with HNO3?
Post by: kimi85 on July 23, 2007, 03:55:00 AM

thank you very much!  ;D