How would you prepare 300 ml of 20 mm napo, buffer, ph = 7.02
day 1: each group will prepare 300 ml of 20 mm nah po, buffer ph 7.0. remember grams of solute (m. w.xmolar concentration of solution liters final volume). this will be our mobile phase when we run our columns. be sure to dissolve your solute in less than the final volume of solvent with vigorous stirring usine deionized water from the container on the benchtop. adjust its ph to 7.0 using solutions of naoh or hcl as needed and then adjust the solution to the final volume. be careful not to let the stirring bar hit the ph meter electrode as it is very fragile and expensive. after adjusting the ph, add deionized water for a final volume of 300 ml. prepare a slurry of the chromatography resin by placing 1.5 grams of sephadex gio resin, the stationary phase, in a clean 50 ml erlenmeyer flask. add 25 ml 20 mm napo4 ph 7.0 by slowly pouring the buffer down the side of the flask. swirl the flask gently to mix the resin and buffer. be careful not to let any of the resin splash up to the wall of the flask as this will result in the loss of some of our stationary phase material. seal the top of your flask with paraffin film, label the container with its contents and the group members' names, and allow the resin to swell by storing in the refrigerator until the next lab session. prepare a chromatography column by filling it with deionized water and let it stand for 5-10 minutes to dissolve anything that may have dried onto the bottom frit. shake vigorously dumping water from the column to remove anything that may have been in the column. repeat the washing process two more times. after the third wash, fill the column with deionized water and let the water flow out of the column though the bottom valve. label your column with group members' names and store until the next lab session.