Make a schematic diagram for the procedure below: A. Constant weighing of the crucibles Bring two porcelain crucibles to constant weight by heating to redness for 15 min over a burner (not including the cover; see Figure 1 for heating set-up). Cool the crucibles briefly on clean Al foil-covered wire gauze at room temperature for 5 min and into the desiccator for 25 minutes. Weigh each crucible accurately on an analytical balance. Repeat procedure a and b until two successive weights agree within ± 0.3 mg, be sure that all oxidizable substances on the entire surface of each crucible have been burned off.

Make a schematic diagram for the procedure below: A. Constant weighing of the crucibles Bring two porcelain crucibles to constant weight by heating to redness for 15 min over a burner (not including the cover; see Figure 1 for heating set-up). Cool the crucibles briefly on clean Al foil-covered wire gauze at room temperature for 5 min and into the desiccator for 25 minutes. Weigh each crucible accurately on an analytical balance. Repeat procedure a and b until two successive weights agree within ± 0.3 mg, be sure that all oxidizable substances on the entire surface of each crucible have been burned off.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter33: Automated Methods Of Analysis

Section: Chapter Questions

Problem 33.8QAP

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