Water is produced from the reaction of hydrogen and oxygen gas, according to the equation below. What is the excess reactant in the reaction of 4.2 moles of hydrogen with 3.0 moles of oxygen?
2H2(g) + O2(g) = 2H2O(l)
Select one:
a.Water
b.Oxygen
c.No excess reactant
d.Hydrogen
2 moles of hydrogen react with 1 mole of oxygen. So, 4.2 moles of hydrogen would need 2.1 moles of oxygen. There are 3.0 moles of oxygen. So, there are 0.9 moles of oxygen in excess.