Question

If 10.0 g of hydrogen gar reacts with 20.0 g of oxygen gas, how much water will be made?

So far this is all i have:
(10.0g H2/1)(2molH2/2.02H2) = 9.0099 mol H2

(20.0g O2/1)(2mol O2/32g O2) = 1.25 mol O2

With the limited reactant being O2

Now what do i do?

I also have to find the yield of only 20.0g of H20 that was made.

Answer 1

Recheck your math onthe moles of H2.

Yes, the limiting reactant was O2, it has less moles.

H2 + 1/2 02>>H2O

so, you only have 1.25moles O2, so you can use up to 2.50 moles H2, and you will get 2.5 moles water.