Term 1 Week 4 - 3E1 SPA Class Datalogging Expt (Cooling Curve of Napthalene)

The practical experiment was conducted to allow the pupils to experience for themselves the cooling effects of napthalene. The use of dataloggers with the temperature probe has helped to allow the measurements of temperature readings every minute.

As compared to the conventional method of recording temperature readings with a mercury thermometer and using an electronic stopwatch, the use of dataloggers has enabled the recording mechanism to be streamlined. The configuration settings of the dataloggers can be preset to allow equal time intervals to be recorded for each temperature reading. Pupils can instead focus more on performing the experiment to improve accuracy of obtaning the data.

The video below shows the 3E1 pupils engaged in the use of temperature probes to take their readings as shown below. The later portion of the video demonstrated vividly how Faye, obtained her data by constantly stirring the napthalene in a systematic manner.

Learning Points:-

1. Pupils need to be familar with the use of dataloggers in taking simple temperature readings. They need to know how to use the icons in the dataloggers to execute the program to obtain the data needed.
2. Teachers need to move around to assist pupils who might have difficulties in performing the experiment and to provide them with the words of encouragement to affirm their belief in themselves.
3. For pupils who did not obtain the 'ideal' cooling curve, it would be a teachable moment to ask them reasons why they did not and to reflect on what happened during the experiment that caused the discrepancy.