The first experiment primarily focused on the uses of laboratory equipment, the importance of experimental measurement and the understanding of scientific measurements. Different measuring instruments were used to determine the densities of Coke and Diet coke in order to evaluate the precision and accuracy of the measurements. Precision refers to the degree of reproducibility; accuracy expresses how closely the measured value correlates to the “true” value of a quantity. However, many errors in measurements can change the precision and accuracy of measured values. Random error, which occurs from minor variations in the quantities measured due to the limitations of the measuring process itself, can affect the precision of a set of measurements. The magnitude of random error can be determined by the standard deviation, a measure of the scatter in the data that reports how many decimal places should be kept in the average. Only one significant figure is used when reporting the standard deviation for the average of repeated measurements; thus, the average is reported to the number of significant figures the standard deviation will allow. Another type of error, systematic errors, can cause readings to be always high or low generally due to mistakes and equipment malfunction. Gross error is caused by committing a personal fault and produces an outlier.
Before performing the procedure, the experiment asked whether the density of Coke differ from the density of Diet coke. It was hypothesize that the densities differ between the beverages due to the different amounts of sugar. According to the results, the density of Coke was 1.04 ± 0.04 and Diet coke 0.99 ± 0.04 when using a pipette. When using a graduated cylinder, the density of Coke was 1.0 ± 0.1 and Diet coke 1.0 ± 0.1; and when using a burette, the density of Coke was 1.03 ± 0.07 and Diet coke 1.01 ± 0.1. Therefore, the densities do differ slightly based on the average results. Because the drinks are composed of different ingredients with different masses, the mass would differ between the two beverages. Density is mass per unit volume; thus the density would not be the same if mass varied due to the different components of the beverages. Changing the volume with constant temperature and pressure would not change the densities of the Coke and Diet coke since density does not depend on the size of the sample; the volume will correlate with the mass. But if somehow the volume could increase without the mass changing, then that will cause the density to be different since density is mass per unit volume. However, if the temperature changed as pressure and mass remained constant, then the density could change if the beverages reached boiling point. At the boiling point, the beverages would turn into gas changing both its mass and volume.
The data also reported difference in densities of the Coke and Diet coke when using different glassware for measuring. The results from the pipette, graduated cylinder, and burette all differ from each other slightly; however, using the pipette produced the most precise measurements seen from the smaller magnitude of its standard deviation. The actual densities of Coke and Diet coke are 1.042g/mL and 0.997g/mL; therefore, the pipette was the most accurate since its measured value corresponds closest to the “true” value.
In part 2 of the experiment, the change in temperature was observed by exposing the temperature probe to the air for 90 seconds, and then covering the tip of the