Drye quantity of primary standard potassim hydrogen phthalate (CHP) for about 2 heat 110°C (Fig. 35-9), and cool in a desiccator. Weigh individual 0,7 to 0.8 g somples (to the nearest 0.Img) into 250 mi conical flasks, and dissolve each in 50 to 75 mL of distilled water. Add 2 drops of phenolphthalein; titrate with base until the pink colour of the indicator persists for 30 seconds (Note). Calculate the concentration of the NaOH solution.

Drye quantity of primary standard potassim hydrogen phthalate (CHP) for about 2 heat 110°C (Fig. 35-9), and cool in a desiccator. Weigh individual 0,7 to 0.8 g somples (to the nearest 0.Img) into 250 mi conical flasks, and dissolve each in 50 to 75 mL of distilled water. Add 2 drops of phenolphthalein; titrate with base until the pink colour of the indicator persists for 30 seconds (Note). Calculate the concentration of the NaOH solution.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter31: Introduction To Analytical Separations

Section: Chapter Questions

Problem 31.19QAP

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