Your titration experiment included phosphoric acid, liqid starch, and Iodine-Potassium-Iodide (IKI) solution. The following information is given: iodine is too weakly colored to act as an effective primary indicator, but it is enhanced by its interaction with stach in a solution. The secondary indicator you will use in this experiment is iodine-starch complex. Iodine-potassium-iodide is the titrant. What acted as the primary indicator in this experiment? The secondary indicator? What was the role of the phosphoric acid? What would happen if you forgot to add it, or added a base instead?

Your titration experiment included phosphoric acid, liqid starch, and Iodine-Potassium-Iodide (IKI) solution. The following information is given: iodine is too weakly colored to act as an effective primary indicator, but it is enhanced by its interaction with stach in a solution. The secondary indicator you will use in this experiment is iodine-starch complex. Iodine-potassium-iodide is the titrant. What acted as the primary indicator in this experiment? The secondary indicator? What was the role of the phosphoric acid? What would happen if you forgot to add it, or added a base instead?

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter20: Molecular Spectroscopy And Photochemistry

Section: Chapter Questions

Problem 67CP

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