Name Experiment 4-Prelab Assignment 1. A 0.219 g sample of an unknown organic acid was titrated with 0.0934 M NaOH; a total of 39.52 mL of the base solution was required to reach the end-point. The acid is known to have 2 carboxyl groups per molecule. What was the molecular weight of the unknown acid? Show all calculations. 2. The melting point of the unknown acid in question 1, above, was found to be 179-182°C and the acid was soluble in water. Which of the following acids is most likely to be the unknown acid? Acid 1 Acid 2 Acid 3 Molecular Mass Solubility 118 g/mole 117 g/mole 120 g/mole water soluble water soluble water soluble Melting Point 147 - 149 °C 170-172 °C 185 186 °C

Name Experiment 4-Prelab Assignment 1. A 0.219 g sample of an unknown organic acid was titrated with 0.0934 M NaOH; a total of 39.52 mL of the base solution was required to reach the end-point. The acid is known to have 2 carboxyl groups per molecule. What was the molecular weight of the unknown acid? Show all calculations. 2. The melting point of the unknown acid in question 1, above, was found to be 179-182°C and the acid was soluble in water. Which of the following acids is most likely to be the unknown acid? Acid 1 Acid 2 Acid 3 Molecular Mass Solubility 118 g/mole 117 g/mole 120 g/mole water soluble water soluble water soluble Melting Point 147 - 149 °C 170-172 °C 185 186 °C

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.35QAP

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