16-26. H₂S was measured by slowly adding 25.00 mL of aqueousH₂S to 25.00 mL of acidified standard 0.010 44 M 15 to precipi-tate elemental sulfur. (If [H₂S]> 0.01 M. then precipitated sulfurtraps some I solution, which is not subsequently titrated.) Theremaining I was titrated with 14.44 mL of 0.009 336 M Na₂S₂O₂.Find the molarity of the H₂S solution. Should starch indicator beadded to this titration at the beginning or just before the endpoint?

Given that Molarity of I-3 = (M1) = 0.01044 M Molarity of Na2S2O3=(M2) = 0.009336 M Volume of…

H₂S to 25.00 mL of acidified standard 0.010 44 M 15 to precip tate elemental sulfur. (If [H₂S]> 0.01 M. then precipitated sulf traps some I solution, which is not subsequently titrated.) T remaining I was titrated with 14.44 mL of 0.009 336 M Na₂S₂C Find the molarity of the H₂S solution. Should starch indicator added to this titration at the beginning or just before the en point?

H₂S to 25.00 mL of acidified standard 0.010 44 M 15 to precip tate elemental sulfur. (If [H₂S]> 0.01 M. then precipitated sulf traps some I solution, which is not subsequently titrated.) T remaining I was titrated with 14.44 mL of 0.009 336 M Na₂S₂C Find the molarity of the H₂S solution. Should starch indicator added to this titration at the beginning or just before the en point?

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

Chapter24: Coulometry

Section: Chapter Questions

Problem 24.12QAP

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