ThermometryTemperature vs. Height of Water, Ethanol, and AcetoneMichael Clements, Nick Christian, Caden CoomesGeneral Chemistry Lab 101ABSTRACTIn this experiment, the focus was to explore and understand the fundamentals of how thermometers are used and operated by measuring the height of columns at different temperatures with each selected liquid, the three liquids used in this experiment are as follows; water, ethanol and acetone. The experiment was executed by assembling an apparatus, changing the temperatures of the water bath in which the Erlenmeyer flask, with each selected liquid, with the addition of ice. The results were conclusive; the liquid that produced the best results was acetone. Therefore, acetone is best suited to be put in thermometers.
IntroductionIn this experiment the different aspects of temperature are shown. Temperature affects all other variables; therefore, it is important to be very accurate and precise with your measurements. With this information, temperature needs to be taken into consideration in experiments because it can alter the results of the experiment.
Temperature is a universal concept that can be applied to a lot of topics, there for it is relevant to this experiment. This experiment was preformed to test the principles of which thermometers operate by looking at the effects of temperature on the volumes of water, acetone and ethanol. Each liquid was heated until it reached a stable state and cooled for data at relatively equal increments. The liquids were heated and cooled independently in order to distinguish each liquid from one to the others. The liquids used were important because their measurements were analyzed and used to understand how temperature and volume are related. For example, the heights of the columns directly related to the temperature and rate of heating or cooling. Therefore, the greater the volume, the higher the temperature and vice versa.Procedure An apparatus was built using a beaker and a ring stand.
The beaker was filled with water and placed on the hot plate to be used as a water bath for the three liquids that were being tested. The Erlenmeyer Flask was then filled with one of the three liquids and placed into the water bath, the hot plate was turned on to 125 degrees Celsius until the temperature of the water bath and column height of the pipet stabilized. Once the two were stable the hot plate was then turned off and a mark was placed on the pipet to mark the first data point, once the temperature dropped 3 degrees Celsius the next mark was made, this process was repeated for a total of five marks on the pipet. ResultsOur results showed that acetone is best suited to be used in thermometers due to its R-squared value. A perfect R-squared value would equal one, acetones was equal to 0.9891. Although with this result, some errors may have negatively affected our results. During the testing of all three liquids ice cubes were inserted into the water to cool it.
Also, during the test of ethanol, the ethanol rose too rapidly and began to reach the top of the column, so the experiment had to be stopped before it spilled over onto the hotplate, but then resumed after the column height decreased enough to carry on. Despite the errors the results of the experiment supported the hypothesis that acetone is the ideal liquid with ethanol coming at a close second at 0.9803.Graph 1:The Graph of Water’s temperature (°C) versus the height of volume (cm) with and R-squared value of 0.9796.Graph 2:The Graph of Ethanol’s temperature (°C) versus the height of volume (cm) with and R-squared value of 0.
9803.Graph 3:The Graph of Acetone’s temperature (°C) versus the height of volume (cm) with and R-squared value of 0.9891.
ConclusionThe results suggest that between the three liquids tested acetone was the liquid with the closest relationship between volume and temperature. Acetone had the closest R-squared value to the ideal value of one. From the results shown throughout the experiment many assumptions could be made to better thermometers in modern day. Current thermometers are filled with mercury to show the temperature.
Unlike mercury, acetone is safer to use. When using thermometers containing mercury, special care must be used to insure the thermometer isn’t broken because the mercury is poisonous where acetone is less of a risk. Mercury was also beneficial because it had a wide range before it would boil or freeze but acetone also has the capability to not freeze at low temperatures or boil at higher temperatures. In conclusion between the three liquids acetone is best suited to be used in thermometers.
