725
Chapter 23 Separation Techniques: Mechanical and Chemical Methods
Procedure
Day 1
1. Mass fi ve chicken wings. Record the mass in a data table.
2. Arrange the wings in a 1000-mL beaker.
3. Add your assigned solution.
Control: 300 mL distilled water
Variation 1: 300 mL distilled water and 15 mL vinegar
Variation 2: 300 mL distilled water and 5 mL salt
4. Place the beaker over medium-high heat and bring the mixture to
a boil. As soon as the mixture boils, turn the heat down to simmer.
5. Place a piece of aluminum foil over the top of the beaker to help
reduce evaporation. Simmer the mixture for 50 minutes to 1 hour
(or until 10 to 15 minutes before the end of the class period).
6. Remove the beaker from the heat with beaker tongs. Use a wax
pencil to label the beaker with your lab group number, class
period, and variation.
7. Remove the chicken wings from the liquid with tongs. Carefully
blot the hot wings dry with paper towels and mass. Record the
mass in your data table.
8. Record the approximate volume of liquid in the beaker.
Record the approximate volume of the yellowish fat layer on
top of the liquid.
9. Place the beaker on a hot pad in the refrigerator.
Day 2
1. Carefully remove any fat from the top of the liquid in the beaker.
The fat should form a solid layer. Loosen the edges with a knife
and lift the fat layer from the beaker.
2. Place the fat layer on waxed paper that has been tared. Mass the
fat. Record the mass in your data table.
3. Place a glass pie plate over a line-spread sheet and use a viscosity
ring to conduct a viscosity test on the chilled liquid. Record the
average of four viscosity readings. The more viscous the liquid
is, the more gelatin it contains.