Stoichiometry
The concept of stoichiometry mainly focuses on answering the following questions:
How can we calculate the amount each chemical needed for a reaction?
How much of each chemical will be produced?
Why is it important to know the amounts of reactants and products?
Do chemists follow a recipe when mixing chemicals?
Steps for performing stoichiometric calculations:
Step 1 Balance the equation for the reaction.
Step 2 Convert the masses of reactants or products to moles.
Step 3 Use the balanced equation to set up the appropriate mole to mole ratio.
Step 4 Use the mole ratio(s) to calculate the number of moles of the
desired reactant or product.
Step 5 Convert from moles back to mass.
Steps for solving stoichiometry problems involving limiting reactants
Step 1 Write and balance the equation for the reactions.
Step 2 Convert known masses of reactants to moles.
Step 3 Using the numbers of moles of reactants and the appropriate mole
ratios, determine which reactant is limiting.
Step 4 Using the amount of the limiting reactant and the appropriate mole
ratios, compute the number of moles of the desired product.
Step 5 Convert from moles of product to grams of product, using the
molar mass (if this is required by the problem).
You can download all of the worksheets that will be used in this unit of stoichiometry by clicking on the following links:
Power point presentation of stoichiometry with audio:
