Tuesday, May 21, 2019
The Law of Conservation of Mass
To identify the gos of a chemic equation. Students need to identify subscribe pets, coefficients, reactants, products, chemic formulas, and chemical symbols 2. To appreciate that scientific discoveries are often the resolving of inquiry. 3. To distinguish between an element, a compound, and a mixture (and between heterogeneous and homogeneous mixtures) 4. To balance a chemical equation in order to prove that the Law of Conservation n of Mass whole kit and boodle duodecimally as well as conceptually 5.To respect that chemicals can be both laboursaving and harmful safety must be a p rarity and the intention of scientists can ladder a large berth in determining if chemicals do sacked hurt or avail humanity 6. To prove tryally the Law of Conservation of Mass that matter is non car go out or destroyed in a chemical reaction Standards NJ CORE CURRICULUM (SCIENCE) measurement 5. 2 ( intuition and society) All stud .NET will develop an understanding of how people of various cu ltures have swear etude to the advancement of wisdom and technology, and how major discoveries and even TTS have advanced science and technology.You can either patsy o t the story or tell the story in your own words. This lesson corresponds with slides 14 on the pop written presentation. Slide 4 contains a short motion picture (approximately 5 minutes) in which h the pass away of Lavisher is discussed. Be sure to mention the connection between his scientist fix work and the necessity of the work for Paris at this cadence in history. Why did he begin this pr Eject? And equivalent questions can be enjoymentd to place this work in its proper historical context. B. Introduce the constabulary of preservation of visual modality prove.Be sure to emphasis zee the purpose of the experiment, mainly, to serve as a analogy to the work of Lavisher. C. Students should perform the activity. You may want to have students perform ram part A in day 1 ND save part B for day 2 unless you ha ve a nice block of clip. D. Following the cobblers last of parts A and B, as well as the conclusion queues ins, discuss the conclusion questions. Specifically, spend time on number 7 and 8. Number 7 asks students to lactate connections between Lavalieres work and what they have done.Number r 8 asks students to brainstorm ideas for other law of conservation of gage experiments. This is is unification because students will be choosing one of these ideas and designing an experiment lat err on. Lesson 2 instruction manual for Teachers Tell the story of Lavalieres work with combustion. Make the connection bet en science and mathematics. Precise measurements were not common until Lavisher m dad them so. Observations, estimations, and generalizations were comm completely lay out in ice once investigations.If you are think on handing out the story rather than tell it be sure to explain what is meant by call. Powering slides 57 pertain to the connection between the law of conservation of megabucks and math, namely balancing equations. Slide 7 is a short video (approximately 5 minutes) in which balancing is explained as well as a short e explanation on naming compounds. Math teachers can teach balancing equations. This ca n be done in edition to the time that we spend balancing equations in science or the mat h teacher may take full responsibility for the balancing of equations. To notwithstanding explain call a demonstration may be valu suitable. You can burn magma enemies and allow students to relieve oneself observations, qualitatively and quantitatively. 2. First, introduce coefficients and subscripts and explain how they can help to s how us how the law of conservation of mass is present in every chemical reaction. Balance a simple equation, the formation of peeing is a good one to start with since just about studs ants are familiar with the chemical formula for water brass.After 1 or much examples have students attempt to balance equations based on l evel of comfort with balancing. Have an reply key posted in the room so that students can enchant that they have correctly equilibrate the aqua actions. There are many websites dedicated to balancing equations. I usually have my much am obvious students Google search a good site and write it on the whiteboard so that realize people who need extra practice or more of a challenge k at present where to go. 3. The selfsameness championship can be completed by students at the end of this less son or at the end of this minutia. Suggest completing it at the end of the unit since you m y introduce more equations within the context of the lessons thus allowing students audit IANAL opportunities to improve their understanding. Lesson 3 Instructions for Teachers Begin this lesson by utter the story of Lavalieres role in discovering oxygen. Be sure to mention the role played by Joseph Priestley. This is a good hazard to disc us how technology, or the lack of technology played a role in the dispute regarding car edit for the discovery.Language barriers, difficulty in traveling far distances, and slow communion definitely played a role. Slides 810 should accompany this less son. Slide 10 contains a short video narrated by Bill Nee in which he discusses, with a m ember of the Chemical heritage Foundation, the story of the work of Lavisher and his role discovering oxygen. Joseph Priestley role in this discovery is in any case mentioned. Have students refer ass to our first law of conservation of mass experiment, specifically conclusion question number 8.Students will now decide on a scientific quests on that relates to the law of conservation of mass and design a controlled experiment in which they attempt to explain data and confirm or refute a theory on the basis of this data. I live that students should be encouraged to choose a question that allows for a lengthy study, requiring multiple measurements. This will reinforce the concepts pert tonal pattern-ling to the law of conservation of mass and allow you, the teacher, to buzz off connections between the law and your other chemistry topics. The final activity is a reflection pertaining to a science demonstration.The bur inning of paper ties in nicely with many aspects of Lavalieres work. See the attachment and ask students to discuss, in words, the similarities, or remnants that they notice. This can be completed in set or it can be a homework assignment. A homework assign meet may be more appropriate if you aroma that students need time to review the story of the e law of conservation of mass that you have told. Towards this end it is also useful to post your notes of the story on your aboard or whatever form of converse you ha eve with students.While I have dedicated the story of Lavatories work to close to of his experiment s there is another story that can be told. Lavisher, who founded a business whose prim responsibility was sight of taxes, was beheaded during the French R evolt Zion. This sad story can be told in science of course, or it can take place in humanities (h story) or in language arts (English). The stow of Lavisher can tie in to the American and F ranch Revolutions for history class. In English class it can be told within the scope of excerpts or entire books that tell stories relating to revolutions.An example might be while e reading Charles Dickens A Tale of Two Cities. The language arts connections offers the teacher an opportunity to focus on the irony that with the beheading of Lavisher the Free inch people removed a psyche who had arguably helped them a great deal and who wool d most likely have make many more significant contributions to the life of Parisian. priming coat Information A the Antoine Lavisher lived and worked in the 18 century, during the time of the French revolution (Grey, 1982).Lavisher is often referred to as the father of modern chemistry (Discovery Education, 2005). Lavalieres first experiment to wind instru ment him toward the e discovery of the law of conservation of mass was part of an experiment to study the CLC manliness of the intoxication water in Paris (Culled, 2005). Lavisher boiled drinking water. According to Culled (2005) the first part of this experiment heterogeneous cleaning a supply flask, drying it, and then carefully weighing it. Next, a finespunly assured ideal of water was poured into the flask and for 101 straight day s heated.The water was heated so that it nevertheless reached the point of boiling. Eventually, self-colored sediment formed on the glass walls of the flask. Culled adds that subsequently weighing the flash k Lavisher concluded that the weight of the flask, the water, and the solid sediment was exactly the same as the mass of the flask and the water with which he started this experiment. If anally, Lavisher removed the water and found that the mass of the water had not chi engaged. However, the mass of the flask and the solid sediment was equa l to the mass of the origin anal clean flask.At this point in the experiment Culled (2005) tells us that Lavisher concluded t hat ascribable to the longer exposure to high temperatures the flask some part of the flask muss t have turned into a new pith, although mass had not been lost. It is worth noting that in his time, many, if not all scientists believed that the e earth was comprised of the four elements of earth, fire, air, and water (Culled, 2005). Du ring the aforementioned(prenominal) experiment Lavisher wondered if water could be converted t o earth, which at the time, Culled states, included any solid substance.Because the mass oft he water in the experiment did not change Lavisher concluded that the manage was that no, water was not converted into earth. A less perceptive scientist would have concluded others sis delinquent to the presence of the particulate. It was his attention to the mass and to exactness in measurement that allow De him to conclude that contrary to what others were espousing, the water did not Chain GE. Grey (1982) adds that the mass of the particulate was exactly equal to the mass that was absent when Lavisher calculated the weight of the dried flask at the end of the 101 days.L bolster included that part of the glass flask had undergone a change due to constant t exposure to high temperatures. Grey adds that this experiment was also significant because SE it lead Lavisher to conclude that just looking at an experiment wasnt bounteous to fin d out what was really going on (p. 40). This experiment, notes Culled (2005) was significant n tot only because it lead Lavisher toward the law of conservation of mass but also beck cause lead Lavisher to the realization that punctilious measurements are critical in experiment notation, something that most scientists did not deem a necessity at the time.Many of Lavalieres experiments, including the water experiment, involved co marring the weight of reactants to the weight of produ cts. In other words, comparing the mass Of the substances he was experimenting with before a reaction to what he had after a reaction. Due to his emphasis on precise measurements Lavisher was able to show that the difference in weight between reactants and products was always small (Culled, 2005).Whew n he initially started these experiments Lavisher was not certain if these tiny differences in mass were due to his inability to make more exact measurements or if matter was indeed bee g created or destroyed, a view that many scientists of the time thought was possible (Grey, 1982). Read about the science of alchemy if you are interested in how and wherefore scientists o f the time believed that this was possible. Its worth noting that Lavisher was eventually able to conclude that matter is not able to be created or destroyed in part because he asked the question, a simple queues n actually, concerning the missing mass.Grey, (1982) notes that He believed there were lots of questions about the world all around him that needed answers. He cherished to look for things no one else had ever found (p. 26). As we learn more regarding the stories be back(prenominal) science discoveries, large and simple, we will notice that almost every one involves in acquisitiveness on the part of the scientist followed by an experimental procedure designed t o answer the question, but it all starts with the question. Background Information B Lavalieres next area of interest was combustion.By the time Lavisher turned to the question of combustion he was well known for his emphasis on precise mess ornaments (Culled, 2005). This was helpful in experiments in which he was attempting to determine if mass had indeed been created, destroyed, or remained the same. Lavalieres combustion experiments consisted of burning metallic elements and compared weights of the metal s before and after heating (Mechanical, 2004). When Lavisher burned sulfur, tin, lead, and phosphorus he found that the m ass of the metal actually increased.However, he also found that when burned in a closed flask the mass of the air in spite of appearance the flask rock-bottom by the exact amount that the metal increased (G ere, 1982). When Lavisher heated the scales, metal bonded with air due to combustion) he found that air was given off as the mass of the metal decreased while the mass of the air in t e container increased by the same amount. Mathematics, which provides quantitative data, allowed Lavisher and later, tot her scientists, to prove that matter was not created or destroyed (Tab, 2004). The word co inspiration room that nothing has been lost.After Lavisher, scientists began to conclude e that in an isolated system (for example, a closed flask) mass is a constant (Johnson, 200 8). We know that a constant does not change. If we are able to find the mass of the system m before anything reacts we can compare it to the mass Of the System after the reaction and the difference should be ze ro, according to Lavisher. Johnson (2008) notes that Lavisher was the first to conclude that the total ma as of a system must be equal to the mass obtained in the beginning of the experiment, regard idles of changes in states of matter.Johnson adds that in France, the law of conservation of m ass is still known as Lavalieres law. We will attempt to prove experiment with chemical r actions in an open system as well as a closed system and yes, we will use mathematics to a assist us in doing so As scientists knowing more about elements and compounds (again, thanks to Lavisher) they ere able to further explain, in more detail, what is indeed happening in chew magical reactions in terms of elements and compounds universe rearranged. Today we know that this accounting is done done balanced equations.Balancing chemical equations is a techno queue employed by scientists in which simple, and sometimes complicated, mathematics IS use d to demonstrate the specific ratios of the substances i nvolved in a chemical aqua Zion. We will also partake in the balancing Of equations and I think that you will find it inter sting to see that what Lavisher, the pioneer, first hypothesized over 200 years ago, because e he dared to ask a question, is now being analyzed and proven in our middle school science e class.Background Information C Lavisher is impute with discovering the element oxygen. He arrived at the co inclusion that oxygen must exist as a result of his interest in combustion. Prior to Lavisher, scientists such as Joseph Priestly who was based in London, had found that when something burned, like metal, the weight of the metal call would be greater than the mass of the origin IANAL substance (Mechanical, 2004). This Priestley explained, was due to the presence of a most absence that was thought to be found in any substance that burns, called p Hollister (Grey, 1982).Scientists reasoned that the added mass (to the call) after something b runner was attributed to phlogis ton. Grey notes that at this time scientists were aware that t the mass of the original piece of metal also decreased, which lead them to the conclusion, alb tit falsely, that phlogiston was transferred when something burns. While most scientists were satisfied with the explanation, others such as Olivia sire found a problem. When metals were burned the mass of the burned metal (called call ) actually increased (Mechanical, 2004).
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