User:Alicia Rasines Mazo/Notebook/CHEM-581 Experimental Chemistry I/2014/09/19

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Tasks for 19 September To begin new synthesis of PVA and 10% w/w PVA-Clay films To finish analysing PVA-Malachite green data To start analysis on X-ray To complete preparation of ionic liquid modified clay To set up experiments for the measurement of absorbance of Mercury and Arsenic by films New film synthesis 1.0022 g 22,000 MW PVA were used to make the PVA polymer film 1.0044 g 22,000 MW PVA and 0.1104 g Na Montmorillonite were used for the synthesis of 10% w/w PVA-Clay polymer film. Completing preparation of ionic liquid modified clay Continued from Set. 17 2014 Ground with mortar Stored in dissecator Measuring the Absorbance of Mercury and Arsenic Film Solution Empty glass vial (g) Glass Vial + film (g) Film weight (g) PVA 150 ppm As 13.0969 13.2069 100 ppm As 13.1262 13.2127 50 ppm As 13.1340 13.2340 150 ppm Hg 13.0145 13.1050 100 ppm Hg 13.0742 13.1521 50 ppm Hg 13.1254 13.2356 10% PVA-Clay 150 ppm As 13.1197 13.2435 100 ppm As 13.0765 13.1374 50 ppm As 13.1298 13.2529 150 ppm Hg 13.1706 13.2172 100 ppm Hg 13.1208 13.1908 50 ppm Hg 13.1493 13.2317 Note: in order to make up the specified dilutions (Table above) of As and Hg, dilutions of stock solutions were prepared. Eleni prepared the arsenic dilutions James and Madeleine prepared the mercury dilutions Dilutions: 0.0499 mol As/L × 74.921 g As/mol × 1000 mg/g = 3738.56 mg/L = 3738.56 ppm (3738.56 ppm)(V)=(150ppm)(50mL) 2mL in 50mL volumetric (3738.56 ppm)(V)=(100ppm)(50mL) 1.34mL in 50mL volumetric (3738.56 ppm)(V)=(50ppm)(50mL) 0.668mL in 50mL volumetric 268 ppm Hg (13.4 mM HgCl2) (268 ppm)(V)=(150 ppm)(50mL) 27.98mL in 50mL volumetric (268 ppm)(V)=(100 ppm)(50mL) 18.66mL in 50mL volumetric (268 ppm)(V)=(50 ppm)(50mL) 9.33mL in 50mL volumetric 10 mL of each solution were poured into glass vials containing the PVA-polymer films Second Analysis of UV-Vis MG data for PVA-polymer film <br.> Used MG calibration curves obtained on Sept. 5 2014 ε615nm=0.1293 M-1cm-1 A=εbc. Solving for concentration: PVA in 2ppm = 0.031/(0.1291 M-1)= 0.240 ppm MG remain in solution (rest absorbed by film) PVA in MG left in solution (ppm) MG absorbed by film (ppm) 2 ppm MG 0.240 1.760 8 ppm MG 0.913 7.087 80 ppm MG 31.70 48.30 200 ppm MG 92.00 108.0 Note that 10 of MG solution were added per vial, so that 2 ppm MG = (1.760 mg MG/L)×0.010L=0.0176 mg MG/film <-- absorbed amount <br.> The weight of the film submerged in 2 ppm MG solution was 0.1060 g. Refer to Sept. 12 2014 for further film weights. (0.0176mg MG/0.01060g film)=0.0166 mg MG/g film 8 ppm: 0.728 mg MG/g film 80 ppm: 4.49 mg MG/g film 200 ppm: 10.8 mg MG/g film Measuring amount of MG absorbed onto glass vial <br.> As in previous section, the molar absorptivity and calibration curve from Sept. 5 2014 were used. <br.> 80 ppm MG in glass vial control: 42.87 ppm were absorbed by glass (Calculations as show in previous section) 0.429 mg MG/glass vial 200 ppm MG in glass vial control: 88.63 ppm were absorbed by glass 0.886 mg MG/glass vial