Express your answer with the appropriate units.

Question

Find the number of moles of water that can be formed if you have 158  of hydrogen gas and 74  of oxygen gas.

Answer 1

First, you must write the correctly balanced equation:

2H₂ + O₂ ==> 2H₂O ... BALANCED EQUATION

This tells us that 2 MOLES of H2 reacts with 1 MOLE of O2 to make 2 MOLES of H2O

In your question, you don't give the units for hydrogen and oxygen, but I'll assume they are moles, so you have 158 moles of H2 and 74 moles of O2.

That being the case, they are present in stoichiometric amounts and neither is in excess and neither is limiting because they react (according to the balanced equation) in a 2:1 mole ratio.

Moles of H2O produced = 158 moles H2O since moles of H2O = moles H2 = 2 x moles O2