if you put aluminium, preferably tin foil, and then add acid in the bottle, it will react violently to create a look of hydrogen. if you close the bottle after pooring the acid in, it will create a cool explosion, be careful of acid sprays though, through the bottle far away!
if you're in the usa you could also just buy C4, it's easier and more practical

Hydrogen Peroxide can be mixed with Hydrochloric Acid and the resulting solution can have copper added into it, after several days the copper can be extracted and it would be Copper Sulfate. This resulting product can be used to make a fire's flame burn green :D

or you can stop being a pussy and drink it straight