The document discusses stoichiometric calculations and limiting reactants. It explains that stoichiometric calculations use the mole ratios from balanced chemical equations to determine the amount of reactants and products. The limiting reactant is the one that limits the amount of product that can be formed. The theoretical yield is the maximum amount of product possible based on the stoichiometry, while the actual yield is the amount experimentally obtained. Percent yield compares the actual and theoretical yields.

1. Stoichiometric CalculationsThe coefficients in the balanced equation give the ratio of moles of reactants and products

2. Stoichiometric Calculations From the mass of Substance A you can use the ratio of the coefficients of A and B to calculate the mass of Substance B formed (if it’s a product) or used (if it’s a reactant)

3. Stoichiometric CalculationsC6H12O6 + 6 O2 6 CO2 + 6 H2O Starting with 1.00 g of C6H12O6… we calculate the moles of C6H12O6… use the coefficients to find the moles of H2O… and then turn the moles of water to grams

4. Sample #1CH4 +2O22H2O + CO2How many moles of CH4 are needed to make 13 moles of water?

5. Sample #2CH4 +2O22H2O + CO2How many moles of water are made from 10g of Oxygen?

6. Sample #3CH4 +2O22H2O + CO2How many grams of water are produced from 100 moles of CH4?

7. Sample #4CH4 +2O22H2O + CO2How many grams of Oxygen are needed in order to produce 200 g of carbon dioxide?

8. Limiting Reactants The limiting reactant is the reactant present in the smallest stoichiometric amount

9. Limiting ReactantsThe limiting reactant is the reactant present in the smallest stoichiometric amountIn other words, it’s the reactant you’ll run out of first (in this case, the H2)

10. Limiting Reactants In the example below, the O2 would be the excess reagent

11. Theoretical YieldThe theoretical yield is the amount of product that can be madeIn other words it’s the amount of product possible as calculated through the stoichiometry problemThis is different from the actual yield, the amount one actually produces and measures

12. Percent YieldActual YieldTheoretical YieldPercent Yield = x 100 A comparison of the amount actually obtained to the amount it was possible to make