Every volumetric instrument has its own error limit and within this area should be the desired volume. In diploma experiments we checked measurement uncertainty, trueness and precision of individual volumetric instrument with statistical tests. In comparison we took volumetric pipettes, burettes, burettes with bead stopcock, volumetric flasks and piston pipettes. Before the experiment we expected, the narrowest area of expanded measurement uncertainty with piston pipettes and the widest one with volumetric flasks. We found out that the area of expanded measurement uncertainty is strongly dependent on the measured volume. In general, we can say that for measurement of small volume (up to 1 mL) piston pipette is the most appropriate. For measurement of larger volume, the volumetric pipette is the most appropriate.
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