Mass and Density Measurements
David Dollimore, Alan C. Samuels · Characterization of Materials · 2003
Abstract The precise measurement of mass is one of the more challenging measurement requirements that materials scientists must deal with. The use of electronic balances has become so widespread and routine that the accurate measurement of mass is often taken for granted. While government institutions such as the National Institutes of Standards and Technology (NIST) and state metrology offices enforce controls in the industrial and legal sectors, no such rigors generally affect the research laboratory. The process of peer review seldom makes assessments of the accuracy of an underlying measurement involved unless an egregious problem is brought to the surface by the reported results. In order to ensure reproducibility, any measurement process in a laboratory should be subjected to a rigorous and frequent calibration routine. This article will describe the options available to the investigator for establishing and executing such a routine; it will define the underlying terms, conditions, and standards, and will suggest appropriate reporting and documenting practices. The measurement of mass, which is a fundamental measurement of the amount of material present, will constitute the bulk of the discussion. However, the measurement of derived properties, particularly density, will also be discussed, as well as some indirect techniques used particularly by materials scientists in the determination of mass and density, such as the quartz crystal microbalance for mass measurement and the analysis of diffraction data for density determination.