Question

Find the number of moles of water that can be formed if you have 182 mol of hydrogen gas and 86 mol of oxygen gas.

Answer 1

Water has a chemical formula of H2O. This means that for every 2 moles of hydrogen and 1 mole of oxygen, one mole of water will be formed.

Note that hydrogen gas and oxygen gas are both biatomic molecules. 

 (1)                   (182 mol H2) x (1 mol H2O/ 1 mol H2) = 182 mol H2O
 (2)                   (86 mol O2) x (2 mol H2O / 1 mol O2) = 172 mol H2O

We choose the smaller number of the two as the answer to this item. Thus, the answer to this question is 172 mol of H2O can be formed out of the given quantities.