Question about aluminium and complex ion formation in water vs in acid

My textbook states, that aluminium reacts with water after dissolving the outer layer with HgCl2, and forms Al(OH)3, an insoluble compound:
2Al + 6H2O = 2 AI(OH)3 + 3H2


In non-oxidizing acids, it forms a salt and hydrogen gas:
2Al + 6HCI = 2AlCI3 + 3H2


But, aluminium is prone to form complexes, so the next reaction states, that in acidic environment, an aquacomplex is formed:
2Al + 6H3O+ + 6H2O = 2[Al(H2O)6]3+ + 3H2


I have tried to research a chemical equation for this complex formation on the internet, and I only found aluminium and water as reactants. No acid present.


**My question:**


* How does the aluminium aquacomplex form, if there is no acid present and if that's not possible, why does it need an acid for the reaction to happen? What role does the acid have?


Thank you




Metallic aluminum is not charged. It has to loose three electrons in order to make the ion $\ce{Al^{3+}}$, which can be complexed later on. An acidic solution is a good way for helping $\ce{Al}$ to loose its electrons, because it produces $\ce{H2}$ which is a gas and leaves the solution, allowing the reaction to proceed with efficiency.


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