Work out limiting reagent instantly with clear inputs, formula shown and shareable results.
The limiting reagent is not simply the one present in the smallest amount - it is the one with the smallest moles-per-coefficient. Dividing each reagent's moles by its balancing coefficient gives how many times the reaction can run on that reagent alone, and the smaller figure caps the reaction. With 3 mol of A at coefficient 1 and 5 mol of B at coefficient 2, B allows only 2.5 runs against A's 3, so B limits.
Extent available per reagent
extent = moles / coefficient
Reaction extent
extent = min(extent A, extent B)
Because a reagent consumed two at a time runs out twice as fast. Raw mole counts ignore that and pick the wrong limiter.
The number of times the balanced equation as written can proceed. Multiply it by any product coefficient to get that product's moles.