The watch glass was removed with the beaker tongs. Using a rubber bulb and a stirring rod to stir the solution continuously, 15.00mL of .25M BaCl2 solution was added to the solution in the beaker. The watch glass is replaced and the solution is keep hot but not boiling for 15 minutes. The precipitate was allowed to settle. When the liquid above the precipitate was clear, the solution was tested for completeness of precipitation when a few drops of BaCl2 solution were added from a pipette.
I lit the burner fuel, placed it under the burner stand, and placed the aluminum cup containing the alum crystals on the burner stand. I then removed and reapplied the burner fuel under the stand to avoid heating the crystals too quickly and splattering. Once the alum crystals started to boil, I then left the burner fuel under the stand and waited and watched for 8 minutes. I then removed the burner fuel, allowed the alum and aluminum cup to cool, and then weighed the mass and recorded the findings in the data table. I repeated the heating and measuring process 2 more times recording the masses in the data table.
First, heat the crucible without its lid, with a strong flame. 6. When the magnesium ribbon starts to burn, cover the crucible with its lid. 7. Using a pair of tongs, carefully raise the lid a little, at intervals.
Look in the water bath on your table for a flask labeled DMA. This flask contains Davis Minimal Agar that has been autoclaved to make it sterile, and is being kept at 47 C to keep it liquefied. 3. Think about these important points in pouring a petri plate before doing it: a) You must work quickly, because once the container of minimal agar is removed from the bath, it will start to harden within 2-3 minutes. b) When pouring agar into the petri dish, pour just enough to fill the dish about half way.
Put the stopper into the boiling tube but do not place the delivery tube under the measuring cylinder yet. 3. Fill the syringe with 1 ml 10% hydrogen peroxide and attach to the syringe needle. 4. Add the hydrogen peroxide to the yeast suspension.
Materials: 250mL Beaker Test Tube Calorimeter Burner, Ring Stand, and Wire Gauze Thermometer Balance Procedure: 1. Prepare an appropriate data table. 2. Fill the 250mL beaker about half full. Place it on the stand and begin heating it to the boiling point (100 degrees Celsius).
Keep the nut positioned (steady) there till the nut loses all energy and the flame dies. 10. Measure the temperature of the water after the nut goes out, and record, your results. 11. Place a watch glass below the copper calorimeter to collect the ashes of the nut, which fall while burning the nut.
Every few minutes, the lid of the crucible was lifted carefully with a tong to see if the magnesium had started to burn and also to left some air enter the crucible to make the experiment more efficient. 6. When the magnesium had completely reacted, the crucible was heated strongly without the lid on for few minutes. Then, the crucible was placed on gauze for it to cool down. 7.
Two drops of water were added to the cooled crucible. The crucible with lid completely on it was placed above the clay triangle. The product was reheated for three minutes. The crucible and product was heated for about five to eight minutes. BE SURE THE CRUCIBLE IS COOL.
6. Turn on the Bunsen burner and allow the water to boil. Steam from the boiler is passed through a ‘steam trap’ to remove any condensed moisture. Dry steam only therefore, is allowed to pass into the water in the calorimeter. 7.