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Mozart
Feb16-06, 04:46 PM
Can I use molar ratios for gasses, solids, and aqueous solutions all in one equation?

For instance: Mg(s) + 2 HCL(aq) -> MgCl2(aq) + H2(g)

Can I say that if i had 2 moles of Mg I would have 2 moles of H2. Does this trick have anything to do with Amedeo Avogadro?

mrjeffy321
Feb16-06, 05:32 PM
Yes, you can do that.

In the reaction you gave,
Mg(s) + 2 HCL(aq) -> MgCl2(aq) + H2(g)
You can see that there is a 1:1 ratio for every mole of Mg reacted to Hydrogen gas produced. So if two moles of Mg were to react, 2 moles of H2 would be produced.

Mozart
Feb16-06, 05:41 PM
Thanks man.

Does this have anything to do with Avogadro's hypothesis?

mrjeffy321
Feb16-06, 06:34 PM
The coeffients in the reaction are meant to show the ratio of each substance being reacted/produced.
The coeffients could mean the number of moles but they could also mean the number of individual atoms/molecules too.