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Help please with Chemisty - Stoiciometry/uneven molar ratios

doctor evil · 2010-01-16 21:30:44

Any idea greatly appreciated! I was using the website below http://www.chembuddy.com/?left=balancing-stoichiometry&right=ratio-proportions and this part confuses me: 4Al + 3O2 -> 2Al2O3 4 moles : 3 moles 2 moles : x moles This time our ratio looks like that: 4 moles : 3 moles = 2 moles : x moles using the same rule to…

16-01-2010 9:30pm

#1

doctor evil

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Any idea greatly appreciated!

I was using the website below

http://www.chembuddy.com/?left=balancing-stoichiometry&right=ratio-proportions

and this part confuses me:

4Al + 3O2 -> 2Al2O3

4 moles : 3 moles

2 moles : x moles

This time our ratio looks like that:

4 moles : 3 moles = 2 moles : x moles

using the same rule to solve the proportion again we get

4x = 6

and x = 1.5 mole. We need 1.5 mole of oxygen to fully react with 1 mole of Al.

Is it not two moles of Al as the ratio has gone down by half?

Booze if you get this far:p

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