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The measurement of mass in different surroundings allows one to measure the density of materials and their interaction with magnetic fields or their temperature dependence. Although most curricula cover the use of analytical scales, many leave out mass measurements in different environments. We describe some of the current instrumentation and applications in this area, including a novel and inexpensive method for measuring magnetic susceptibility.

The gasometric analysis of nitrogen produced in a reaction between sodium nitrite, NaNO2, and sulfamic acid, H(NH2)SO3, provides an alternative to more common general chemistry experiments used to study the ideal gas law, such as the experiment in which magnesium is reacted with hydrochloric acid. This experiment, in which the percent sodium nitrite of a sample is determined with the use of equipment commonly found in a general chemistry laboratory, was first published in 1946, and data culled over the last several years show that modifications to the procedure, specifically replacing a glass vial with a gel capsule, have improved accuracy and precision in this classic laboratory exercise. In addition to the ideal gas law, this experiment provides students with an opportunity to analyze data using principles and concepts that constitute core topics often presented in the first semester of general chemistry, such as stoichiometry, redox equations, Dalton’s law of partial pressures, the vapor pressure of water, and barometric pressure.