Tuesday, March 15, 2011

Chemical Reactions and Temperature Lab Investigation

Title: Chemical Reactions and Temperature Lab Investigation

Problem: How does temperature affect chemical reactions, i.e. alka-seltzer tablets.

Hypothesis: When the beaker with the alka-seltzer tablet is heated to 50 degrees Celsius, the process will speed up significantly, and vice versa for the cold temperature trial.

Materials: 500 mL Beaker
1 Graduated cylinder
1 Vernier Lab Quest Mini temperature probe with Logger Lite software disk
3 Alka-seltzer tablets
1 Watch or clock
1 Hot plate (set on high)
3-4 Ice Cubes

Results and Conclusion: The cold temperature was tested first, in this particular instance. When the ice cubes were dropped, the water level only reached 175 mL, whereas the instructions in the procedures section suggested to use the dimensions of 266 mL. Nonetheless, this was one of the variables that might have affected the outcomes in the end ramifications. Once this was recorded, the tablet was gently dropped into the beaker so that no spillage would occur and cause for extra clean-up, and the beaker was scanned for any significant observations. One of the surveillances caught on to the seltzer’s patterns; the effervescence systematically raised to the surface until ice crystals formed. Approximately one minute into the experiment, the tablet began to rise about half-way as if to only skim the surface to see what the outside temperature was. It did not fully peak until later when it was too late, and the lozenge was disintegrated at one minute and thirty seconds. After the tablet was gone completely, a very active bubble residue was left in layers in the 500 mL beaker. The general uprising of bubbles continued. Larger bubbles that dwelled on the bottom of the container rose in a choppy manner alongside the edges of the lipped cylindrical glass, in contrast to the minuscule bubbles that gently ascended at a consistent pace in the center of the beaker. At the six minute mark, most of the activity had slowed down, and culminated in an accumulation of large bubbles on the perimeter. These globules concluded with ice crystals as a consequence of the cold temperature. To illustrate my point, batteries discharge quicker in a cold temperature than they normally would in a warm temperature. This is because reactions occur slower in tense, chilly climates than contracted, warm climates.



To conclude the first test, the gradual audio end (while the tablet fizzed, it emitted a definite audio susurration) died down about 3 minutes after the tablet was completely deteriorated. Temperature measurements were recorded at the start to be 13.4 C (and was also the highest temperature), with a low point of 6.2 (at 79 seconds), and a final product of 7.1 at 156 seconds.



The next step descending from a freezing temperature is room temperature. This test commenced with a degree of intensity of heat at 22.4 C. Once the alka-seltzer tablet plunged into the not-so icy water (due to the fact that it was cleaned out between each trial for the most accurate results possibly accumulated), the sizzle of the pastille reacted at a much faster rate, almost at double speed than the first. With a new record, the alka-seltzer fizzled until its end at roughly 30 seconds. It also pinnacled with a hazy water appearance visible to the naked eye. Taking into consideration the pattern of bubbles the previous test accrued, this trial also had stratums, ranging from thick to thin (with a mixture of both large and small bubbles). The difference comes in when discussing the placement of the ice crystals and effervescence. The medium sized bubbled formed a small patch of ice crystals directly in the center of the beaker and served as an unstable crust on top of the water-seltzer solution. All the while, petite bubbles gathered on the bottom with the exception of a slight ice crystal circumference, and gradually raised to the top in their normal, uniform velocity. Unlike the first experiment, this lab pilot had an almost definite audio end (even though it was louder while in the process), meaning that it had a precise crepitating elimination point that corresponded realistically with the termination of the alka-seltzer tablet. Once again, numeric results had a low extremity of 21.8 C at the end of the beta test (84 seconds), and an extended end point of 22.8 C at around 5 minutes.



Opposing both predecessors, the hot temperature test snowballed different results altogether. Following the directions in the procedures section, the container was set on the bunsen burner to reach the necessary temperature. Waiting for the solvent in the beaker with the probe peeping through the topmost echelon on the glass to reach 50 degrees Celsius was the one and only dull point in the third trial. Once the alka-seltzer tablet was added and the beaker was removed from the hot plate, a fragrance was omitted in the atmosphere that was similar to that of a burning liquid. And in less than 15 seconds, the capsule was completely disintegrated and practically dead silent, as far as fizzing goes. This was also the time that it took for all but a few of the bubbles to raise up to their repeated destination. There are always a few exceptions, nonetheless, those that could have been prevented due to variables blocking the pathway of a perfect science experiment. These variables may include the inconsistent position of which the temperature probe was placed in this and previous trials, as well as taking into consideration the tablet. Whether the tablet was whole or not could have impacted the experiment because the inside was exposed to oxygen, light, and any dust floating in the air at that particular time and place. On the other hand, the hot temperature test also cumulated specific heat intensity results including (but not limited to) the following: starting at 22.3 C, fabricating a high peak of 53.8 C at 1.5 seconds after recording, and finally an end conclusion of 50.2 C at 57.5 seconds. Therefore, the above hypothesis can be officially approved as not just theoretically, but also realistically correct.



1 comment:

  1. Research lab is a perfect place to experiment on different projects and information you shared is good.
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