Partial Thermal Degradation of Carbon Dioxide formed

advertisement
PARTIAL THERMAL DEGRADATION OF CARBON DIOXIDE FORMED
SACCHARIDES WITH PROTEIN INCLUSIONS
John Paul Jones, Okaloosa ~ December 1999
Reagents:
Sucrose
3 M Glucose Solution
Mixed Esters (solidified)
NaCl
# 0.02 Protein Pellets
NaHCO3
4-hydroxy-3 methoxybenzaldehyde
Distilled water (fresh)
Equipment:
Ring Stand
Ring
1 - 250 mL receptacle (approx. 16 oz. can)
1 - 300 mL receptacle (approx. 32 oz. can)
Bunsen Burner
Glass Stirring Rod
Electronic Balance
Aluminum Foil
Wax Paper
Thermometer
All equipment coming in contact with reagents must be washed with soap and water
and rinsed completely with distilled water prior to lab activity using standard laboratory
practice.
1.
2.
3.
4.
5.
6.
7.
8.
9.
Into a clean 250-mL receptacle, weigh out 75.0 grams of sucrose.
Transfer to a clean 400-mL receptacle.
Into the 250mL receptacle weigh out 62.0 grams of 3 Molar glucose solution
Pour the glucose into the 400-mL receptacle. Use a total of 19.0 mL of
newly opened distilled water in two batches to rinse the small receptacle and add
rinsing to the large receptacle.
Heat mixture slowly. Stir constantly. Bring to a boil. Use as cool a flame as
possible. Boil continuously for 5-7 minutes.
Weigh out 9.5 grams of solidified mixed esters on waxed paper
Add the mixed esters to the boiling glucose-sucrose solution
Continue to heat and stir.
Weigh out .3 grams NaCl and 55.0 grams of protein pellets onto waxed paper
When solution temperature reaches 138 C, add the NaCl and protein pellets
(This has consistently been a problem in this experiment. If you do not have a device which is
able to register a temperature this high, you must take a small drop of the sample of your hot
solution, drop it into a beaker of cold water and make sure that the drop solidifies to a hard
crystalline consistency.)
10.
11.
12.
13.
14.
15.
Continue to stir.
Weigh out 3.7 grams of NaHCO3 on waxed paper, and obtain 1.3mL of
4-hydroxy-3 methoxybenzaldehyde. Prepare a pad of folded paper towels.
Lightly coat a 0.30 m square of Al foil with solidified mixed esters
When temperature reaches 154C, remove the flame, place receptacle on pad.
While one person holds the receptacle and is prepared to stir, have the other
partner add the benzaldehyde and NaHCO3. Stir vigorously. As the mixture
nears the top of the receptacle, pour evenly and thinly on the Al foil
Allow to cool slowly and observe.
Download