Posted by Rara on .
How many milliliters of a 0.3 molar HCl
solution are needed to react completely with
8 grams of zinc according to the following
equation?
? HCl + ? Zn → ? ZnCl2 + ? H2
Answer in units of mL

DR.BOB HELP CHEMISTRY! 
drwls,
First, you need to balance the equation. Can you do that?
You will need two moles of HCl per mole of zinc.
Ask yourself this question:
How many moles of zinc is 8 grams? 
DR.BOB HELP CHEMISTRY! 
Rara,
I balanced it and got:
2HCL + Zn > ZnCl2 + H2
And then to find moles I did: 8/65.37 and got 0.1124 moles.
But now I'm stuck, what do I do next? 
DR.BOB HELP CHEMISTRY! 
drwls,
You are doing fine so far.
You need 2*0.1124 = 0.2248 moles of HCl.
One liter of the solution contains 0.3 moles of HCl.
You need a bit less than a liter of the acid solution. 
DR.BOB HELP CHEMISTRY! 
Rara,
Okay, so would I divide 0.3 by 0.2248? >_> I'm sorry, my chemistry is my weakest subject. :(

DR.BOB HELP CHEMISTRY! 
drwls,
No, you need less than a liter.