Limiting Reagent Problems
Now lets consider limiting reagent problems. You should remember those. They are the problems that are a little more difficult than the kind that you were just working with because you have to decide which of two starting chemicals to base your calculations on. Limiting reagent problems that are solved using balanced equations are very much the same as what you were working with a few lessons ago. It's just that you now use the balanced equation to give you the relationship between the chemicals.
There is a sequence of steps that should be taken to solve these types of problems. First, write an equation for the reaction and balance it. Second, determine the mole and weight relationships among the chemicals in the reaction. Third, determine the limiting reagent in the same manner you did a few lessons ago. Fourth, carry out the necessary calculations using the mole and weight relationships determined from the balanced equation.
Two examples are worked through for you on the pages in this section, one with weights (example 7 from your workbook) and one with moles (example 8 from your workbook). Look through them and then try your hand at the practice problems that follow (example 9 from your workbook). The answers to those practice problem are on the last page of this section.
Distance Learning questions
Clackamas Community College