[megan7880]

Can anyone please help me on this?

[Donaldson Tan]

No visible change will be observed.

Although Al is highly placed in the Metal Reactivity Series, metallic Al wont react aq HCl because in its natural state, the Al sheet would be coated with an inert layer of amphoteric Aluminum Oxide. This layer provides sacrificial protection against corrosion. It prevents Al from being in actual contact with the acid. Hence, the typical metal-acid reaction won;t occur.

[jdurg]

No visible change will be observed.

Although Al is highly placed in the Metal Reactivity Series, metallic Al wont react aq HCl because in its natural state, the Al sheet would be coated with an inert layer of amphoteric Aluminum Oxide. This layer provides sacrificial protection against corrosion. It prevents Al from being in actual contact with the acid. Hence, the typical metal-acid reaction won;t occur.

Sorry Geo, but you couldn't be more incorrect.    Aluminum metal will most definitely react with a solution of hydrochloric acid.  The aluminum-oxide layer protects the metal from reaction against water, but hydrochloric acid is a different story.  HCl will eat through that layer after a while.  So while the reaction won't proceed very fastly, it will eventually take off.  It generally takes a few minutes for the reaction to get going if the HCl isn't concentrated.  In a dilute solution, it can take three to five minutes for the HCl to remove the protective layer.  Once the layer is gone, however, the reaction will proceed very quickly.  

[Donaldson Tan]

heh! u r right.. forgot that aluminum oxide can be used up by HCl