Analysis of a mixture consisting of NaOH + NażCO3 + inert matter gives the following data: Sample portions are titrated. With one portion, an end point with phenolphthalein is obtained in cold solution, with 44.52 mL of 0.5000 N HCI. The other portion requires 46.53 mL of the acid for an end point with methyl orange. Calculate the percentage composition of the original sample. 10.00 g. Its aqueous solution is diluted to 250.0 mL and two separate 25.00 mL %3D

Analysis of a mixture consisting of NaOH + NażCO3 + inert matter gives the following data: Sample portions are titrated. With one portion, an end point with phenolphthalein is obtained in cold solution, with 44.52 mL of 0.5000 N HCI. The other portion requires 46.53 mL of the acid for an end point with methyl orange. Calculate the percentage composition of the original sample. 10.00 g. Its aqueous solution is diluted to 250.0 mL and two separate 25.00 mL %3D

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter31: Introduction To Analytical Separations

Section: Chapter Questions

Problem 31.21QAP

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It is required to know the concentration of an aqueous solution of H2SO4 that appeared in the laboratoryChemistry III and it's unlabeled. To this end, a student of analytical chemistry carried out the followingProcedure: He took 5.00 mL of a fresh and standardized solution of 0.525M NaOH and brought them to a250.0 mL balloon to be completed with distilled water. Subsequently, he poured 15.00 mL of the solutionH2SO4 of unknown concentration in an Erlenmeyer flask and added 2 drops of phenolphthalein.Using a burette filled with the last NaOH solution, he noticed that when adding 39.40 mL of the hydroxidethe Erlenmeyer solution reached a faint but permanent pink. With the above dataDetermine the concentration and pH of the H2SO4 solution.
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