Limiting Reactants and Percent Yield

Limiting reactant- reactant that limits the amount of the other reactant that can combine and the amount of product that can form in a chemical reaction

Excess reactant- The substance that is not used up completely in a reaction

Silicon Dioxide(quartz) is usually quite unreactive but reacts readily with hydrogen fluoride according to the following equation.

SiO₂(s) + 4HF (g) ---> SiF₄(g) + 2H₂)(l)

If 6.0 mol HF is added to 4.5 mol SiO₂, which is the limiting reactant?

Theoretical yield- maximum amount of product that can be produced from a given amount of reactant

Actual Yield- the measured amount of a product obtained from a reaction

Percentage yield- the ratio of the actual yield to the theoretical yield, multiplied by 100

percentage yield

Chorobenzane, C₆H₅Cl, is used in the production of many important chemicals, such as aspirin, dyes, and disinfectants. ONe industrial method of preparing chlorobenzane is to react to benzene, C₆H₆, with chlorine, as represented by the following equation.

C₆H₆(l) + Cl₂(g) ----> C₆H₅Cl(l) + HCl(g)

When 36.8g C₆H₆ reacts with an excess of Cl₂, the actual yield of C₆H₅Cl is 38.8 g. What is the percentge yield of C₆H₅Cl?