3) Place the penny tails up 4) Place the pipette over the letter “c” in “one cent” 5) Place the pipette 5 inches above the penny 6) Begin to slowly squeeze the solution out of the pipette, over the letter “c” while counting the numbers of drops until the solution spills out from the surface of the penny. 7) Record data of how many drops of green mysterious solution could be held and the observations made. 8) When the solution spills out of the penny, dry off the penny. 9) Repeat steps 2-9 but over the Lincoln icon mark in the very center of the penny (be sure to use the same exact penny) The controlled conditions for this experiment included; a clean table surface, same penny, same person, and same pipette. The manipulated variable is where the person holding the pipette dropped the green mysterious solution on the “c” of “one cent” on the back or the very middle of the penny.
Cylinder was rinsed with distilled water. * * 2. 2.0 ppm standard: 2.00 mL of 10.0 ppm phosphate solution was placed in a 25 mL graduated cylinder and diluted to exactly the 10 mL mark with distilled water then poured into a plastic cup labeled 2. Cylinder was rinsed with distilled water. * 3.
Make the new dilution series. Remember to start with salt concentration where the egg first floated. (If you don't have enough solution from the original serial dilution, make some more by starting from the stock solution.) 8. As before, test the egg in each cup, starting with the lowest salt concentration.
Try to rinse the precipitate in the funnel until the pink color is gone 12. Place funnel in the drier provided until it is completely dry 13. Let cool to room temperature 14. Weigh the funnel and record the weight 15. Subtract the weight of the funnel and the filter paper from this weight to get the weight of the precipitate Results: wt.
The MgSo4 absorbed the last traces of water the ether solution. The solution was completely dry when it appeared crystal clear and MgSO4 floated in the liquid, when swirled. If solution is cloudy, more drops of MgSO4 were to be added until solution was completely dropped. 5) We decanted the solution from the solid MgSO4 into a 50 or 100 ml round bottom flask. 6) The ether was removed using the rotary evaporator.
Obtain a clean-dry test tube. Place 0.3g of the unknown substance in the test tube. Next, add 10mL of distilled water to the test tube. Mix with a stirring rod until unknown is dissolved. 2.
Place a 1.0 cm piece of magnesium ribbon (get from instructor) in a clean/dry test tube. Using a plastic pipette, carefully add 10 drops of 6.0 M or 3.0 M hydrochloric acid to the test tube. Record your observations. Make sure you feel the bottom of the test tube. 5a.
The flasks were thoroughly cleaned with distilled water. 3. Samples of the Ammonium Persulfate ((NH4)2S2O8), Potassium Iodide (KI), Ammonium Sulfate ((NH4)2S2O4), Potassium Nitrate (KNO3), Sodium Thiosulfate (Na2S2O3), and Starch were placed in separate Erlenmeyer flasks. 4. Each flask was labeled according to its content (i.e.
Bring the contents of the distillation flask to a gentle reflux (i.e., vapors are condensing in the first ¼ to 1/3 of the vertical condenser and dripping constantly back into the flask below). Maintain this reflux for 10 minutes, then increase the heat in order to distill the liquid into the collection flask, then the column, and even the distillation head with aluminum foil (shiny side IN). Continue distillation of the cyclohexene product until the volume in the distillation flask is reduced to about 1 mL. Ask the instructor to assist you in removing the heat source and sand bath for the almost empty flask; use Ove Gloves and/or clamps to avoid burns. |
Turn on the hot plate to a medium heat. Wait until all the liquid has evaporated from the substance and then record the color of the dried substance. 6) Repeat steps 1-5 using each of the three other substances. NOTE: Make sure to wipe down all the materials before they are reused. Compounds | Solubility in Water | Solubility in Alcohol | Color if Soluble in H₂O | Conductivity(Scale 1-4) | Color When Dry | Melting Point (°F) | Sucrose | Yes | No | Transparent | Medium (2) | Brown | 366.8 | Sodium Chloride | Yes | No | Transparent | High (3) | Crystallized, Clear | 1474 | Sodium Carbonate | Yes | No | Mostly Transparent | High (3) | White | 1564 | Salicylic Acid | No | Yes | N/A | High (3) | White | 318.2