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Anhydrous ammonia, the most widely used nitrogen (N) fertilizer in production agriculture, can be subject to extensive losses by volatilization if it is not carefully applied. A laboratory exercise was developed for a senior-level soil nutrient management class to help students learn the impact of rate, application depth,andsoiltextureonammonia(NH3)volatilizationfromanhydrous ammonia. Sand and loam soil textures were evaluated at 5-, 10-, and 15-cm application depths and 112 and 224 kg N ha -1 rates of NH3, simulated by reacting ammonium chloride (NH4Cl) and sodium hydroxide (NaOH). Soil-retained ammonium (NH4) was measured in a potassium chloride (KCl) extraction of the soil 1 wk after treatment. Students developed a table and graphs that showed trends in NH3 loss with respect to applicationdepth,soiltexture,andfertilizerrate.Lossesranged from 85% for the high N rate applied at 5 cm in sandy soil to 1.0% for the low rate applied at 15 cm in loam soil. The exercise helped students identify causes of NH3 loss associated with anhydrous ammonia application. ANHYDROUS AMMONIA is the most widely used nitrogen (N) fertilizerinproductionagriculturetodaywithmorethan15billionkgproducedannuallyforagriculturaluseintheUSA(The Fertilizer Inst., 2000). Its high N percentage (82%) and relatively low cost make it an important N fertilizer source. A common concern associated with the application of anhydrous ammonia is the loss of N by volatilization. Several factors such as soil pH, soil moisture, soil texture, and depth of application play a large role in the amount of N lost by