Stoichiometry problems can be solved by either the factor unit method or by proportions. In this tutorial, all problems will be solved by the factor unit method. Most students will make fewer mistakes using the factor unit method than by using proportions.

The following represent some of the more common variations of these problems.

· How many grams of ethane (C2H6) will react with 64 g of oxygen? The formula mass of ethane is 30 amu and the formula mass of oxygen is 32 amu. How do you begin to solve this problem? J

2 C2H6 + 7 O2 ® 4 CO2 + 6 H2O

· How many grams of ethane are required to produce 22 g of carbon dioxide? The formula mass of carbon dioxide is 44 g. How do you begin to solve this problem? J

· If 15 g of ethane react with 80 g of oxygen, how many grams of water will be produced? The formula mass of water is 18 g. How do you begin to solve this problem? J

· Given that 1 mole of any gas will occupy 22.4 liters at standard temperature and pressure, how many liters of carbon dioxide at STP will be formed when 4 moles of ethane react completely with excess oxygen? How do you begin to solve this problem? J

Return to the problem tutorial. J

Copyright © August 2000 by Richard C. Banks...all rights reserved.