1. Good Morning 10/20/2015 Starter: Why does a candle burn for so long? Today we Working on Candle Lab This lab is a great way to show the scientific method and it has some great physical & chemical changes.

2. Candle Lab Purpose: To determine why a candle can burn for so long? What is the fuel? What makes it burn?

3. Before going to the lab You will find many materials to test out various hypothesis, please be very careful, I’d prefer not to have to use the fire extinguisher today. Once you come up with a procedure for your hypothesis show me and I’ll light your candle. Those who finish early can try to develop additional labs that would explore similar situations Get your goggles (you won’t need aprons)

4. Hypothesis #1: the Wick Procedure: Data (Observation): Results: Conclusion: Take a piece of string and see if it can burn as long The string burned really quickly The string (wick) can not be the fuel The hypothesis was wrong

5. Hypothesis #2: Solid wax Procedure: Data (Observation): Results: Conclusion: Light the wooden splint on fire and try to burn the solid wax. The solid wax melted The solid wax can not be the fuel The hypothesis was wrong

6. Hypothesis #3: liquid wax Procedure: Data (Observation): Results: Conclusion: Light the wooden splint on fire and dip it into a pool of liqid wax. The liquid wax put the flame out The liquid wax can not be the fuel The hypothesis was wrong

7. Hypothesis #4: Vapor wax Procedure: Data (Observe): Results: Conclusion: Light the wooden splint on fire and hold it just above a pool of liquid wax. The flame kept burning without consuming the wood. The vapor wax must be the fuel The hypothesis was right

8. Notes on Classroom discussion & Final Conclusion The a candle burns by melting solid wax, (physical change) vaporizing the liquid wax (physical change) and then combusting (combined with O 2 ) the vapor (chemical change). Final Conclusion: The fuel for a candle is the vapor wax.