Chemistry Reference
In-Depth Information
Safety Note
Goggles must be worn at all times during this
experiment. Use caution with flames and combustible fuels. please
review and follow the safety guidelines at the beginning of this volume.
Procedure
1. Fill a beaker with 100 ml of cold water.
2. Create a lid for the beaker by cutting a piece of Styrofoam™ that is
large enough to cover the entire top of the beaker.
3. Carefully push a thermometer through the center of your
Styrofoam™ lid so that the tip will be fully immersed in the water
but will not touch the bottom or side of the beaker. Tape the
thermometer in place.
4. Set up a ring clamp on the ring stand. Place the beaker with lid and
thermometer into the ring (see Figure 1).
5. Position a spirit burner directly beneath the beaker so that the flame
will slightly touch the bottom of the beaker when it is lit.
6. Wrap the apparatus (beaker and burner) with several layers of
aluminum foil to insulate it. Leave some small air holes so that
oxygen will be available for the combustion process. Arrange the
aluminum foil with a flap or door that will enable you exchange the
spirit burners and refill the beaker of water between trials.
7. Choose an alcohol from the available selection of fuels. Fill the
spirit burner about one-quarter full of the chosen fuel.
8. Use the electronic balance to find the initial mass of the spirit
burner and fuel and record the mass on Data Table 1.
9. Record the initial temperature of the water (shown on the
thermometer) in the beaker on Data Table 1.
10. Position the spirit burner underneath the beaker. Use matches to
light the wick of the burner. Quickly replace the insulating layers of
aluminum foil so that no heat will be lost.
11. Allow the fuel to burn and heat the water in the beaker. Monitor the
temperature of the water until it remains stable for 1 minute (min).
Record the final temperature on Data Table 1.
12. Extinguish the spirit burner and allow it to cool. Find the final mass
of the spirit burner and record it on Data Table 1.
