Depression Objective: Determine the molecular mass of an unknown substance by finding the change in freezing point of a solvent when the unknown substance is dissolved in it. Qualitative Data: Trials BHT (g) Cetyl –Alcohol (g) Unknown substance (g) Melting Temperature 1 0.48 g 0 0 69.3 2 0.46 g 0.09 g 0 66.9 3 0.49 g 0 0.11 g 53.7 Analysis: 1.) Determine ___ for the solution of cetyl alcohol and of the unknown substance in BHT. 2.) Calculate the molality of the cetyl alcohol solution and use
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3 3.4 Determination of Melting Point 3 4 Results and Calculation 4 4.1 Mass 4 4.2 Percent yield 4 4.3 Melting Point 4 4.4 Appearance 4 5 Discussion 5 6 Conclusion 5 References R1 Synopsis This report is based on preparation and recrystallization of aspirin. The objective of the experiment is to conduct the synthesis of aspirin and reinforce the skills of recrystallization and technique of melting point determination. Both
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The Khmer Rouge with its leader Pol Pot‚ seized Cambodia in 1975. Year zero is declared‚ in effect Cambodia was isolated from the rest of the world‚ and cities‚ money‚ private property and religion were abolished. In hopes of making Cambodia become an agrarian utopia‚ Khmer Rouge forced the people who lives in the cities of Phnom Pehn and Battambang to leave their homes and were dictated to work in the labor camps‚ where people are abused and executed. About 2 million people died during their reign
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Aleena Joseph‚ Melting Away‚ 2017‚ Oil on canvas‚ 16 x 20 inches It is common knowledge that the world has been changing and over time‚ it will come to an end and that the reason for those changes is humans. It is due to the excessive amounts of harmful human activities that the world is almost melting away. Global issues such as climate change or global warming may sound unrealistic‚ however‚ the events occurring around the world proves that these issues are real indeed. Just as an example‚ London
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Within the article "Glaciers Disappear in Before & after Photos" from the live science website‚ and "The Effects of Melting Ice Glaciers" from the buzzle website‚ they express the important role glaciers play as one of earth’s natural resources. Glaciers not only provide for about 75% of the world’s fresh water. They are also a source of electricity and a replenishing
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completes the statement or answers the question. ____ 11. The phase change that is the reverse of sublimation is a. deposition c. condensation. b. vaporization. d. melting. ____ 12. The phase change in which a substance changes from a solid to a gas or vapor without changing to a liquid first is a. melting. c. deposition. b. sublimation. d. vaporization. ____ 13. If a solid piece of naphthalene is heated and remains at 80°C until it is completely melted‚ you know that
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substance’s freezing point and the first few molecules cluster together into a crystal lattice to form a tiny quantity of solid. As long as both solid and liquid phases are present at the freezing point‚ the rate of crystallization equals the rate of melting and there is a dynamic equilibrium. When a solution freezes‚ a few molecules of solvent cluster together to form pure solid solvent and a dynamic equilibrium is set up between the solution and the solid solvent. In the case of a solution‚ the molecules
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Cambodian Muslims‚ Christians‚ Buddhists were indicted for their beliefs. Permanence was an important alibi for torture‚ imprisonment‚ and killings. (“Cambodian Genocide Facts and Timeline: A Clear Account”). The Khmer Rouge party made the attempt to “Pol Pot” just to nationalize and centralize the “peasant farming society” in Cambodia overnight: this action ending up in gradual devastation of over twenty-five percent of the population in just a few short years. Well over 750‚000 civilians lost their lives
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Damian Perez Austin English II 5 October 2014 Rena’s Promise Essay Does history repeat itself? There are many different cases that have had leaders and governments that have used their power to commit crimes against humanity. There are many occasions before the 1990’s all over the world that have had genocide against a certain population. Some of the most famous crimes against humanity that are still talked about today are Communist in China‚ Khmer Rouge in Cambodia‚ and Muslim militia and the
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Comparison to the Average College Student Data First and foremost‚ I was very interested in how many similarities and differences that there was between myself and the average college student. I found the similarities interesting because I do not feel that I spend my time evenly in each area‚ like I assumed the average college student did. I was most proud of myself in the sleeping category‚ seeing that I get‚ on average‚ 0.6 hours more sleep than the average college student. I think that my strict
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