User:Elizabeth Ghias/Notebook/Experimental Chemistry/2012/10/15

Experimental Chemistry

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Objective To remake the glutaraldehyde films containing clay, to make a film with porphyrin, and to measure sodium ion content using a sodium electrode. Description Making Glutaraldehyde Films 4 films were made - (1)PVOH/glutaraldehyde, (2)PVOH/Na-MT/glutaraldehyde, (3)PVOH/100% CEC Clay/glutaraldehyde, and (4)PVOH/porphyrin/glutaraldehyde Film 1 was made by dissolving 1 g PVOH in 7 mL of water. Once all the PVOH had dissolved, 1 mL of glutaraldehyde was added. The solution was stirred for 5 minutes and then was poured into a dish and allowed to evaporate until Wednesday. Actual amount of PVOH = 1.0059 g Film 2 was made by dissolving 1 g PVOH and 0.1 g Na-MT in 7 mL of water. Once they had dissolved, 1 mL of glutaraldehyde was added. The solution was allowed to mix for 5 minuntes and then was poured into a dish and allowed to evaporate until Wednesday. Actual amount of PVOH = 1.0021 g, actual amount of Na-MT = 0.1016 g Film 3 was made by dissolving 1 g PVOH and 0.1 g 100% CEC clay in 7 mL of water. Once they had dissolved, 1 mL of glutaraldehyde was added. The solution was allowed to stir for 5 minuntes and then was poured into a dish and allowed to evaporate until Wednesday. Actual amount of PVOH added = 1.0014 g, actual amount of 100% CEC clay = 0.1004 g. Film 4 was made by dissolving 1 g PVOH in 7 mL of water. Once it dissolved, 1 mL of glutaraldehyde and 1 mL of porphyrin was added. The solution was allowed to mix for 5 minutes and then was poured into a dish and allowed to evaporate until Wednesday. Determining the Sodium Ion Content The sodium ion content of the sodium standards ([]= 0.25,1,3,7,9 ppm) were measured An 0.1 mL of ionic strength adjuster (4M solution containing NaOH) was added to a 3 mL of each solution to be tested, so that the pH of each solution would fall in the range of pH = 8 to 10. The electrode was placed into each of the solutions and were allowed to equilibrate for 2 minutes. This procedure was done for all of standards Data Sodium Electrode Results Sample Negative Voltage (mV) Water + Adjuster ***** 0.25 ppm + Adjuster 175.1 1 ppm + Adjuster 170 3 ppm + Adjuster 158.5 7 ppm + Adjuster 146.4 9 ppm + Adjuster 139.8 All of the voltage values should be negative. The table feature would not allow the negative signs to be included. Notes For an ion selective electrode, higher concentrations have more negative voltages. The film containing the porphyrin had a light pink color to it.