Calibrating a Volumetric Flask
المؤلف:
D. A. Skoog, F. J.Holler, D M. West, and S. R. Crouch
المصدر:
Fundamentals of Analytical Chemistry
الجزء والصفحة:
9th ed- p45
8-8-2016
1372
Calibrating a Volumetric Flask
Weigh the clean, dry flask to the nearest milligram. Then fill to the mark with equilibrated water and reweigh. With the aid of Table 1-1, calculate the volume contained.
Calibrating a Volumetric Flask Relative to a Pipet
The calibration of a volumetric flask relative to a pipet provides an excellent method for partitioning a sample into aliquots. These directions are for a 50-mL pipet and a 500-mL volumetric flask. Other combinations of volumes are equally convenient. Carefully transfer ten 50-mL aliquots from the pipet to a dry 500-mL volumetric flask. Mark the location of the meniscus with a gummed label. Cover with a label varnish to ensure permanence.
Dilution to the label mark permits the same pipet to deliver precisely a one-tenth aliquot of the solution in the flask. Note that recalibration is necessary if another pipet is used.
Table 1-1
الاكثر قراءة في التحليل النوعي والكمي
اخر الاخبار
اخبار العتبة العباسية المقدسة
