PROBLEM 4 OF LIMITING REAGENT SET PROBLEM 4 OF LIMITING REAGENT SET. 2S (s) + 3O2 (g)  2SO3 (g) FIRST DETERMINE IF THERE IS A LIMITING REAGENT. / FIND MOLES OF ALUMINUM METAL FIND MOLES OF OXYGEN GAS. MOLES = MASS/GFM S MOLES = 1.0 g s/ 32.04g/mol MOLES = 0.031191 mol S MOLES = MASS/GFM O2 MOLES = 1.0 g O2 / 32.00g/mol MOLES = 0.03125mol O2 S = 2 = 0.031191 , O2 3 0.03125 .666 < 1 The actual ratio is larger than the theoretical, therefore the actual ratio fraction is too large, the denominator is to small, O2 limiting.

2S (s) + 3O2 (g)  2SO3 (g) STEP 1 Identify known (the substance that can be converted to moles), choose the correct equation to convert to moles. MOLES = MASS/GFM O2 MOLES = 1.0 g O2 / 32.00g/mol MOLES = 0.03125mol O2 STEP 2 RATIO known to objective, O2 = 3 = 0.03125 , SO3 2 X X = 0.020833 mol SO3 STEP 3 Convert Objective to required units. MOLES = MASS/GFM SO3 0.020833 mol= mass/ 80.06g/mol Mass = 1.314 g SO3 % yield = experimental/theoretical 0.80 / 1.667 =47.9% = 48%