AP Chemistryeasymcq1 pt
2H₂ + O₂ → 2H₂O. With 4.0 mol H₂ and 3.0 mol O₂, which is the limiting reactant?
A.H₂
B.O₂
C.Neither; both run out together
D.Both are limiting
Explanation
Core Concept
4.0 mol H₂ needs 2.0 mol O₂; 3.0 mol O₂ is available, so oxygen is in excess and hydrogen runs out first. Compare moles to the 2:1 coefficient ratio, never compare raw mole numbers.
Correct Answer
AH₂
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