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Gift
May 8, 2007, 03:34 PM
I'm so confused with the equation. But I got 15.3L as an answer.I don't know if it's correct.

"How much Zinc must react in order to form 15.5L of hydrogen, H2 (g),at 32.0c and 115 kPa"?

Zn(s)+H2SO4 => ZnSO4(aq)+H2(g):)

Capuchin
May 10, 2007, 04:10 AM
Erm, well let me start with the obvious, Zinc is a solid, you can't measure it in litres.

From the equation you can see that 1 mole of H2 will form from 1 mole of Zinc.

You need to work out how many moles of H2 you have (PV = nRT), then you know how many moles of Zn you need, and then you can work out how many grams of Zn you need.

Let me know how you get on, I'll be happy to check your result.

Gift
May 10, 2007, 04:09 PM
I got .692mole of Zn that is needed but I don't know how to continue working. Which equation should I use?:)

Capuchin
May 10, 2007, 10:29 PM
Well you know how much a mole of zn weighs right? It's on the periodic table!

Gift
May 11, 2007, 03:42 AM
Oh yeahhh
I totally forget that!
Thanks a lot!! ;)