Question

Laboratory Questions Circle the questions that have been assigned. 1. Part A.1. The KIO, sample was not sur klo, sample was not sufficiently dried. Will the reported molar concentration of the KIO, solution (Part B.3) be too high, too low, or unaffected? Explain. 2. Part A.1. The mass of KIO, used to prepare he mass of KIO, used to renare the solution was measured to be 0.585 g instead of the calculated 0.535 a. Will the molar concentration of th me molar concentration of the KIO, solution be greater or less than 0.01 M KIO,7 Explain. b. As a result of this (now) prepared K of this (now) prepared KIO, solution, will more or less volume of KIO, solution be used for the vitamin C analysis? Explain. D.I. The NaHCO, solution is omitted in an analysis of the sample. Will the reported amount of ascorbic acid in the sample be too high, too low, or unaffected? Explain. Part C.1. Explain why the mass of KI (-1 g), and the volume of starch (-2 mL) are only approximate even though the analysis is quantitative. 3. Part C.2. After adding the standard solution of KIO, to the prepared analyte, the sample solution never forms the deep- blue color. What modification of the Experimental Procedure or error corrected can be made in order to complete the analysis? 6. Part C.2. The deep-blue color of the I, starch complex does not appear but a yellow-brown does appear! What next? Should you continue titrating with the standard KIO, solution or discard the sample? Explain. 7. Part C.2. The final buret reading is read and recorded as 27.43 mL instead of the correct 28.43 mL. Will the reported amount of ascorbic acid in the sample be too high or too low? Explain.

Answer 1

1. Since Torelarity Mass T melar mass xVdune Since KI03 damlo loas not doiud Cmplotely and Rerce obAwed mas will ka faher therafore wwed igher toro 2.a) Meaurad o585g will ha amelordy indead e -5359 Since mas has oen meadwrod igh ond Rence the elubon will ka gater than 0.01 M KI03 b Molariy Volume Hence noco loss Volune o KIO3 will be Clbe d fvitanin-c tibation Becaun both tholaruty ond Velune ard wersly related