3 mol O2. The decomposition of 2 mol of KClO3 produces 3 mol of O2.
(a) Use the balanced equation to find the molar ratio of O2:KClO3.
Molar ratio = 3 mol O2:2 mol KClO3
(b) Use the molar ratio to calculate the moles of O2.
Moles of O2 = 2 mol KClO3 x (3 mol O2/2 mol KClO3) = 3 mol O2