An approximately 0.1 M NaOH solution is made by adding 4.0 g of solid NaOH to 1000 mL. of water. The precise concentration of the solution is determined by titrating the NaOH against portions of a weak acid, potassium acid phthalate (KHP) obtained from the National Bureau of Standards and certified as being 99.99% pure. The KHP samples are weighed by difference on a balance. How would the calculated NaOH concentration be affected (in comparison with the true concentration), if: (does it become greater, smaller, or unchanged) 1. The KHP was not dried prior to weighing? 2. The balance always read high, but in proportion to the weight recorded?

An approximately 0.1 M NaOH solution is made by adding 4.0 g of solid NaOH to 1000 mL. of water. The precise concentration of the solution is determined by titrating the NaOH against portions of a weak acid, potassium acid phthalate (KHP) obtained from the National Bureau of Standards and certified as being 99.99% pure. The KHP samples are weighed by difference on a balance. How would the calculated NaOH concentration be affected (in comparison with the true concentration), if: (does it become greater, smaller, or unchanged) 1. The KHP was not dried prior to weighing? 2. The balance always read high, but in proportion to the weight recorded?

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter4: Types Of Chemical Reactions And Solution Stoichiometry

Section: Chapter Questions

Problem 152CP

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