10 litros y medio de leche cuantos mililitros contiene?
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Hello

The balance chemical reaction is 2Al + 6HCl  -à 2AlCl3 + 3H2 Assuming excess amount of HCl because it is not given   Mole Al reacted = 13.5 g ( 1 mole/ 27 g) = 0.5 mole Al   
Mole H2 = 0.5 mol Al ( 3 mole H2 / 2 mole Al)  = 0.75 mole H2   
since at STP then 1 mole gas occupies 22.414 L volume H2 = 0.75 mole (22.414 L / mol) = 16.8105 L H2
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