Exp039

Dominican University student project January 30, 2009 Annie Jacobsen ** Open Notebook Science Solubility Challenge ** Solute: maleic acid Solute SMILES: O=C(O)\C=C/C(=O)O Solute type: carboxylic acid Chemspider link: http://www.chemspider.com/Search.aspx?q=maleic+acid Solvent: ethanol Solvent SMILES: OCC Solvent density: 0.789 g/mL Solvent type: alcohol Chemspider link (solvent): http://www.chemspider.com/Search.aspx?q=ethanol // * These values were obtained 63.5 hours after the vials were removed from the water bath to ensure complete evaporation of the solvent. // // See “Final Procedure.” // //Final Procedure// 1. Supplies were obtained and cleaned. 2. 25 mL of ethanol was measured with a graduated cylinder and poured into a 125 mL Erlenmeyer flask 3. Maleic acid was added with a plastic spoon and mixed by swirling and stirring with a stirring rod. 4. Once saturated, approximately 6 mL of the solution was added to each of 4 centrifuge tubes (capacity of 4-6 mL). The tubes were centrifuged for about 2 minutes with an EH Sargent & Co. 117-volt centrifuge. 5. A syringe was used to transfer 5 mL of the clarified solution to each of 4 individually tared vials, labeled 1-4. 6. The mass of each vial plus its 5 mL of solution was obtained. All mass measurements for this experiment were conducted on an Acculab balance (#21850227). 7. The test tubes were added to a hot water bath and removed after 15 minutes. 8. The mass of each vial plus its solute was obtained. 9. After 63.5 hours, the vials containing the solute were weighed again. This final mass measurement is denoted in the above table and is the mass upon which all solubility calculations are based.
 * Average Solubility: 3.410 mol/L **
 * 43.94 g/100 g ethanol **
 * || ** Vial 1 ** || ** Vial 2 ** || ** Vial 3 ** || ** Vial 4 ** || ** Standard Deviation ** ||
 * ** Mass of empty vessel ** || 12.810 g || 12.835 g || 12.795 g || 12.841 g ||^  ||
 * ** Volume of solution ** || 5.0 mL || 5.0 mL || 5.0 mL || 5.0 mL ||^  ||
 * ** Mass of vessel + solution ** || 17.350 g || 17.264 g || 17.329 g || 17.361 g ||^  ||
 * ** Mass of vessel + solute* ** || 14.820 g || 14.789 g || 14.800 g || 14.791 g ||^  ||
 * ** Mass of solute ** || 2.010 g || 1.954 g || 2.005 g || 1.950 g ||^  ||
 * ** Mass of solution ** || 4.540 g || 4.429 g || 4.534 g || 4.520 g ||^  ||
 * ** Solubility (//volume//) ** || 0.4020 g/mL || 0.3908 g/mL || 0.4010 g/mL || 0.3900 g/mL || ± 0.3712%  ||
 * ** Solubility (//mass//) **// per 100 g solvent // || 44.27 g || 44.12 g || 44.22 g || 43.14 g || ± 30.91%  ||
 * ** Solubility (Mvolume) ** || 3.463 mol/L || 3.367 mol/L || 3.454 mol/L || 3.359 mol/L || ± 3.196%  ||
 * ** Solubility (Mmass) **// per 1 kg solvent // || 3.813 mol || 3.800 mol || 3.809 mol || 3.716 mol || ± 2.655%  ||