This demonstration is designed to illustrate the concept of limiting reagent in a spectacular way. Via a series of experiments where the amount of vinegar is fixed and the amount of NaHCO3 is gradually increased, the volume of CO2 generated from the reaction varies corresponding to the amount of NaHCO3 until it reaches the point where the CO2 volume remains constant no matter how much NaHCO3 is used. The observation clearly leads to the conclusion that before the equivalence point, NaHCO3 is the limiting reagent and vinegar becomes the limiting reagent afterwards. This demonstration is appropriate for introductory high school chemistry level and recommended for a large classroom presentation.
More Information
Citation
Artdej, Romklao; Thongpanchang, Tienthong. J. Chem. Educ.2008, 85, 1382.
Experiments, laboratory exercises, lecture demonstrations, and other descriptions of the use of chemicals, apparatus, instruments, computers, and computer interfaces are presented in the Journal of Chemical Education as illustrative of new or improved ideas or concepts in chemistry instruction and are directed at qualified teachers. Although every effort is made to assure and encourage safe practices and safe use of chemicals, the Journal of Chemical Education cannot assume responsibility for uses made of its published materials. Many chemicals are hazardous. Precautions for the safe use of hazardous chemicals and directions for their proper disposal are described in the Material Safety Data Sheets and on the labels. We strongly urge all those planning to use materials from our pages to make choices and to develop procedures for laboratory and classroom safety in accordance with local needs and situations.
Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.
In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first.
Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants.
Caution! 
