Entropy Changes Regarding the Second Law of Thermodynamics Lab 18: Experiments 1 & 2 Abigail RodgersJune 30, 20172nd Law Of Thermodynamics and Entropy Abstract: In the first experiment, students were able to investigate the Second Law of Thermodynamics using heat flow, as seen when heat was transferred from hot objects to cold objects. Students saw that heat flows from hot items to cold items, but not the opposite direction. In Experiment 2, students used two dice to test the probability of states. Students observed that when there were more possible combinations, the higher the total occurrences there were. Students were able to investigate laws of thermodynamics, as well as the flow of entropy throughthese two experiments.2nd Law Of Thermodynamics and Entropy Introduction:Background: The Second Law of thermodynamics involves the transfer of heat, but is more specific about the direction in which heat flows. Thermodynamics states that heat flows from hot objects to cold objects and that the process is not irreversible. When cups of hot and cold water are placed next to each other, heat will transfer from the hot cup to the cold cup, as students will begin to see in the experiment. Entropy can be defined two ways. The first was involves a transfer of heat, like in Experiment 1. Entropy can also be quantified by probably, such as dice rolls, which students will see in Experiment 2. Objective: The learning objectives of this lab is to calculate the entropy of states of a simple system, experimentally test the probability of states, and explain why the order of an isolated system must increase. Hypothesis: According to the Second Law of Thermodynamics, in Experiment 1, the heat will be transferred from the hot water to the cold hand, but not vice versa. Due to entropy, students will see a higher probability in the combinations that have more than one possible outcome, such as the numbers 5,6,7 and 8.2nd Law Of Thermodynamics and Entropy Methods: For Experiment 1, students used a permanent marker to label the Styrofoam cup “Ice Water” and it was filled with ice and water. Then a second Styrofoam cup was labeled “Room Temperature” and was filled with water and allowed to rest for 5 minutes. The last cup was labeled “Hot Water” and was filled with hot water from the sink. One finger was held in the cup for thirty seconds and then immediately placed in the room temperature cup. The observations were recorded. One finger was then placed in the ice water cup for thirty seconds, and then immediately placed in the room temperature cup. Observations for this trial were also recorded. For the second experiment, students took the dice and rolled them on a flat surface and recorded the macro-state by placing a tally mark in Table 3. This step was repeated 99 more times to get a distribution map of the probability of macro-states for the two dice. Results: In the first experiment with the cups of water, students were able to observe heat flow. When the student’s finger was placed into the hot cup and then into the room temperature cup, heat was first transferred to the student's finger and then into the room temperature cup. When the finger was first placed in the ice water cup and then the room temperature cup, heat flowed from the room temperature cup, back to the student's finger to warm it up. In the second experiment, 100 trials were conducted of rolling tow dice and the results were recorded in Table 3. The most common combination of numbers rolled was six, closely followed by seven, and five and eight were almost equally behind. Discussion: According to the Second Law of Thermodynamics and Entropy, the heat in the experiment flowed from the warmer objects to the cooler objects. This was seen when the heat2nd Law Of Thermodynamics and Entropy went from the warm water cup, to the student's finger, then back into the room temperature watercup. Also, heat flowed from the room temperature cup to the student's finger after it was placed in the ice cup. The student was able to feel the heat transfer in their fingers due to the warm and cold sensations. There could have been error occur, including not having warm enough water, or enough ice in the colder cup. In Experiment 2, students saw that the more possible combinations of the number, the more times it was rolled. Out of the 100 trials, six was rolled the most, because six can be formedthe easiest. The numbers such as two, three, eleven and twelve were not rolled as often due to thefact that their combinations occurred less frequently. There could have been random error to occur in this experiment. Conclusion:Through the two experiments, students were able to see the Second Law of Thermodynamics taking place in real world scenarios. Students saw which way heat flowed, from warmer objects to cooler objects, in the first experiment. In the second experiment, studentsobserved that events with more possible outcomes, end up having a higher number of total occurrences through the dice roll experiment. Entropy is one of the driving forces of the universe, and in this lab, student's were able to see how entropy flows and apply it to real world situations. References: Urone, P. P., Himrichs, R., Dirks, K., & Sharma, M. (2013). College Physics. Houston, TX: Openstax College, Rice University. EScience Labs. (n.d.). Retrieved June 07, 2017, from http://www.esciencelabs.com/2nd Law Of Thermodynamics and Entropy Tables, Charts and
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