Science Lesson Plan: Chemical Changes of Matter

Lesson Goals - Using the technology of the Civil War Rifleman as a backdrop, students will learn about chemical changes in matter. This lesson assumes a working knowledge of the states of matter. Students will observe that during combustion, matter is not lost or gained, but simply changes. In this case, when black powder is ignited, is seems to disappear, but creates smoke (carbon dioxide) and water vapor.

Lesson Objectives

Students will watch and describe what occurs during combustion of gunpowder

Students will reevaluate the misconception that matter simply "disappears" during combustion.

Material List

- Black powder (gunpowder and smokeless powder will not provide the necessary visual of smoke)

- "Wand" type lighter

- Glass beaker

- Fire extinguisher

- Goggles

Procedure / Methods

1) Pose the inquiry question (When a Civil War Rifleman fires his rifle, the gun powder in his rifle disappears. Where does it go?) Have someone record the answers for later comparison.

2) Pour out a small measure of powder, and ignite it.

3) Have the class record their observations

4) Restate the inquiry question. Have someone record the answers.

5) Pour out another measure of powder. Place the beaker upside down over the powder, almost covering it. Ignite the powder.

6) Have the students observe the beaker. They should note the presence of smoke and moisture.

7) Have the class record their observations

8) Restate the inquiry question. Have someone record the answers.

Questioning Script for Experiment:

1) "Is this a physical or a chemical change? What evidence do you have?" Possible Answers: "Chemical because new substances were formed" "Physical (on first ignition) because nothing is there."

2) (To be asked after step 2) "Where did the powder go?" Possible answers: "It disappeared." "It turned into smoke."

3) (To be asked after step 6) "Where did the moisture come from?" Possible answers: "The powder turned into water." "There was moisture in the powder already and it turned into steam."

4) "What else did you observe other than smoke and moisture during the ignitions?" Possible answers: "A flash of fire." "Heat."

5) "What differences did you observe between the first and second ignition? Why do you think that is important?" Possible answers: "Moisture formation was visible." "The moisture was caused by the reaction.

6) "What sort of problems could the smoke and moisture cause for a rifleman?" Possible answers: "Can't have ignition with lots of moisture." "Smoke makes it hard to see."

Explanation of experiment: Carbon dioxide and water are produced during combustion. When done out in the open, both compounds are in a gaseous state and are often hard to see. When the beaker is held over the reaction, the water and gas are more easily viewed. This shows that the powder does not actually "disappear," but is changed into two other compounds, with energy released as heat and light.

Academic Areas: Science, Social Studies, Language Arts

Illinois State Standards

11.A.3f Interpret and represent results of an analysis to produce findings

12.C.3a Explain interactions of energy with matter including changes of state and conservation of mass and energy.

1.B.3a Preview reading materials, make predictions, and relate reading to information from other sources.

Modifications This activity is not easily modified as it already encompasses several of the multiple intelligences.