Answer:- 168 moles of water are formed.
Solution:- The balanced equation for the formation of water from hydrogen and oxygen gases is:
[tex]2H_2(g)+O_2(g)\rightarrow 2H_2O(l)[/tex]
From this equation hydrogen and oxygen react in 2:1 mol ratio.
We have been given with 178 moles of hydrogen and 84 moles of oxygen. We need to figure out the limiting reactant first. For this let's either calculate the moles of oxygen required to react completely with 178 moles of hydrogen or the moles of hydrogen required to react completely with 84 moles of oxygen.
Let's say we calculate the moles of oxygen required to react completely with 178 moles of hydrogen:
[tex]178molH_2(\frac{1molO_2}{2molH_2})[/tex]
= [tex]89molO_2[/tex]
From the above calculations, 89 moles of oxygen are required to react completely with 178 moles of hydrogen but only 84 moles of oxygen are available, It means oxygen is the limiting reactant and the product yield depends on it.
There is 1:2 mol ratio between oxygen and water. Let's calculate the moles of water for given 84 moles of oxygen:
[tex]84molO_2(\frac{2molH_2O}{1molO_2})[/tex]
= [tex]168molH_2O[/tex]
So, the reaction of 178 moles of hydrogen and 84 moles of oxygen gives 168 moles of water.
