What is fuel?, A companion lab for the ChemComm book Options

[Tom_Crumrine]

What makes a fuel?

Objective: For students to investigate what are the components of a fuel and to experiment with what makes burning work.

Background: Every year in a course called Chemistry and its Applications we look at the chemistry of fuel. This fits well with the research I will be observing in the arctic because during this unit we discuss the carbon cycle and how fuel fits into that process. Currently my students are in the middle of a unit and I decided to create this little activity to refresh their memories after a week long spring break. We went outside for the activity and it took about 15 minutes. The inspiration came from the Learn to Return training with Brian Horner.

Materials: cotton balls, matches, metal pan or aluminum foil, chapstick (I also had other household fuel sources like peanut butter and vegetable oil for those students who wanted to try the experiment with other materials.), stopwatch or watch with second hand, goggles.



Procedure: I demonstrated spreading out a cotton ball and burning it. While doing the demonstration I asked them some general questions about burning: Why was spreading the cotton out useful? What would happen if I squeezed up the ball and then lit it? I burned the cotton ball in a metal pan. This pan provided wind protection and made sure that the small fire was contained.

After demonstrating I gave students two cotton balls. I asked them to time the buring of one of them. Then I asked them to take a little chapstick and mix it in with the second cotton ball. They then timed the burning of that cotton ball chapstick mixture. (Those students who moved quickly were able to try the other household substances with a third cotton ball.)

Back in the classroom we compiled the class data. From here you could have them make graphs, average the data or other things. We used the data to have a discussion about fuels and burning. For me the hidden agenda is to get students to think about what types of things may be fuels and to consider new substances that could be used for fuels. I am hoping that this will help when we make biodiesel later in the unit.