Have you ever sat around a campfire or watched flames flicker in a fireplace? The burning of wood is a chemical reaction – a process that changes one set of chemicals into another set of chemicals. A chemical reaction always involves changes in chemical bonds that join atoms in compounds. The elements or compounds that enter into a chemical reaction are called reactants. The elements or compounds produced by a chemical reaction are called products. As wood burns, molecules of cellulose are broken down and combine with oxygen to form carbon dioxide and water vapor, and energy is released.
1. What are the reactants when wood burns?
2. What are the products when wood burns?
3. What kinds of energy are given off when wood burns?
4. Wood doesn’t burn all by itself. What must you do to start a fire? What does this mean in terms of energy?
5. Once the fire gets started, it keeps burning. Why don’t you need to keep restarting the fire?
