Introduction
Three elements must be present at the same time for a flame to burn:
If any of these elements are reduced or removed then a flame will be extinguished. This experiment uses the DrDAQ’s Oxygen In Air sensor to monitor the oxygen level required to keep a flame burning.
Warning — as this experiment requires the use of matches adult supervision will be required.
Equipment required (See Fig. 1)
Fig1: Setup
Equipment setup
- Connect the DrDAQ data logger to the parallel port.
- Attach the oxygen and temperature sensors to the top of the glass jar. Keep all the sensor leads a safe distance away from the candle.
- Connect the oxygen in air sensor DD103 and the temperature sensor DD100 to external sockets 1 and 2.
- Configure PicoLog to take a sample every 250 milliseconds for 200 samples.
Carrying out the experiment
- Start PicoLog recording
- Light the candle
- Place the glass jar with the sensors attached over the bowl of water (As seen in Fig. 1)
- Hold the DrDAQ’s onboard light sensor to the glass jar
- Once the candle has been extinguished leave the experiment to settle for a couple of seconds
Questions
- What two by-products were produced by the flame?
- At what point did the candle extinguish?
- How does the graph show you that the candle uses oxygen?
- What oxygen level is required to keep the candle burning?
