Fair test
The test is repeated twice for each temperature of glycerol. The experiment will start at the lowest temperature 14˚C. To ensure that the results are unbiased, all variables, except for the temperature will be kept constant e.g. amount of glycerol poured into tube through to flask. The type of fluid used also needs to be the same, therefore only glycerol will be used. Furthermore to make it a fair test, the same temperatures will be used for both tests, to give an accurate average result. When the glycerol is poured into the tube through to the conical flask, a stopwatch will be started as soon as it leaves the container. This will be done for each temperature to ensure no anomalous results occur.
Safety precautions
PREPARE
• Clear all surfaces before beginning work.
• Read through the whole experiment before you start.
• Identify hazardous procedures and anticipate dangers.
PROTECT YOURSELF
• Follow all directions step by step; do only one procedure at a time.
• Make sure that there is adequate ventilation.
• Do not mess about.
• Wear and goggles.
• Do not wear contact lenses, open shoes, and loose clothing; do not wear your hair loose. Make sure there are no obstructions whilst experimenting incase of falls, trips etc.
• Keep floor and work space neat, clean, and dry.
• Clean up spills immediately.
• Do not taste any substances tested unless expressly permitted to do so by a science teacher in charge.
USE EQUIPMENT WITH CARE
• Set up apparatus far from the edge of the desk.
• Push Bunsen burner tube carefully onto a gas releaser.
• Clean glassware before and after use.
• Check glassware for scratches, cracks, and sharp edges.
• Clean up broken glassware immediately.
Apparatus
- Gauze
- Tripod
- Bunsen burner
- Boss and clamp
- Retort stand
-
Bench mat
- Stopwatch
- Conical flask
- Funnel
- Thermometer
- Beaker
Method
To begin the experiment, firstly I gathered the required apparatus (as shown above) and arranged it as necessary. Followed by the glycerol being measured into the required amounts needed, the temperature was then recorded, as a starter. It was then poured through the funnel, and the stop watch was immediately started, the time was then recorded, after the glycerol had been completely poured into the conical flask. Afterwards the glycerol was heated to the required temperature and then poured again, stopwatch started as soon as the glycerol started to dribble out of the funnel into the conical flask. This was done for all of the temperatures twice. Next the results that were recorded, were placed into a table.
This is the first set of results:
This is the second set of results:
Analysis
By looking at my graph I can definitely tell my prediction was correct. It shows that the hotter the glycerol the smaller amount of time it takes for the glycerol to pass through the funnel into the conical flask. I can now tell that I have no anomalous results as it worked out as I had planned, e.g. whilst heating the glycerol this gives more energy to the molecules, so making the glycerol less dense and easier to run, it will be quicker than at room temperature or just generally cooler. My graph also shows, that it doesn’t take a lot of heat to make the molecules gain energy, and therefore making the glycerol more liquefied, as the molecules have gained more space as well as energy. This shows that glycerol is in fact, easy to heat, and although it can remain a liquid for a long period of time, it is possible that it doesn’t have a very high boiling point.
Evaluation
Overall, the experiment was successful as it reached its target, I have now got the precise information to qualify my prediction. Although it was correct it could have been improved in many ways i.e. making sure no glycerol was wasted whilst pouring it back into the beaker, as it needed to be used again. There was excess glycerol kept inside the conical flask, this could have been avoided by cleaning it out for every temperature, even if it meant using more and more glycerol each time, as it would have been more accurate. The stopwatch was not started exactly at the right time, either because the person who started it did not have quick enough reactions, or it was in fact the stop watch that was not very accurate. This could be avoided by linking the experiment to the computer, which can give extremely accurate results and a better overall idea on how temperature affects the viscosity of glycerol.
