Question

If you have Hydrochloric acid, how many grams of aluminum must you use to produce 57.0 L of hydrogen at STP?

2Al(s)+6HCl(aq) --> 3H2(g)+2AlCl3(aq)

Answer 1

Just follow the steps in this example.
http://www.jiskha.com/science/chemistry/stoichiometry.html

Answer 2

I ended up getting 42.718333 not rounded to sig figs but does the excess of hydrochloric acid have anything to do with the answer and what about the STP?

Answer 3

I have something like 45. something and the problem says nothing about excess HCl; however, it won't work this way unless HCl IS IN excess.
You use the 57.0 L at STP to calculate moles H2. Remember that 1 mole of a gas at STP occupies 22.4 L; therefore, 57.0/22.4 = ?? moles H2.
Then ?? moles H2 x (2 moles Al/3 moles H2) = ?? moles H2 x (2/3) = moles Al and that times molar mass Al = about 45 g or so Al.

Answer 4

You are true and correct.Even, DMK's First MLA is a vninaar. DMK symbol " Rising SUN" is the symbol of SS Ramaswamy padayachi's party symbol. It was annadurai,who gained the support of A.Govindswamy padayachi( Mugaiyur MLA) and got the symbol. Even today, many old vninaars believe " Rising SUN" is the padayachi's symbol.