Chemistry Lab writing Discussion

Le Chatelier’s Principle

Learning Team D

Week 4 Assignment - Week 3 Lab Discussion

Equilibrium is a state of a chemical reaction that occurs when reactants turning into products is occurring at the same rate as products turning into reactants. When a system at equilibrium is put under stress it will correct itself to relieve the stress and reestablish equilibrium, known as Le Chatelier’s Principle. It states that a system that undergoes a change in temperature, concentration, volume, or partial pressure will react to counter the change and establish a new equilibrium. If the quantity of reactants is increased, the system will shift right and make more product. If we increase the temperature, it is similar to increasing the amount of heat in the reaction. If such reaction is endothermic than heat is a reactant. If such a reaction is exothermic, than the heat is product. If the pressure is raised in a gas system, the system will act to reduce the pressure. This lab demonstrated the theory …..(state the main theme) As a group, Team D performed each lab individually and compared the results, discussed what could be changed in the lab to make it better, and added some real world applications of the experiment. Other than the theme – intro ok

Comparing Results:

During part one, all students but one decided the equilibrium would shift to the right when HCl was added. This occurs when adding HCl, the hydronium ions will combine with the hydroxide which causes it shift to the right. Once again, all students besides one agreed that when EDTA was added to the solution, the equilibrium would shift to the right. In the last section of part one, all students believed the reaction was endothermic, but really the reaction was exothermic due to the magenta solution staying the same color in the cold water bath, but turning a pale color in the hot water bath. Why would be interesting …..

In Part Two of the experiment, all students agreed the equilibrium would shift to the left when Na2SO4 was added to the solution because the color changed to a light color. I would have liked a discussion of the “chemistry” When NaHSO4 was added to the solution, team members agreed that the equilibrium would shift to the right due to the color changing to a darker color. Last but not least, all members agreed that the reaction was exothermic, even though no student could see a difference in color in the water baths. Why?

What we would do different:

Even though the lab was pretty straight forward, the only section the students would agree on to change is during the water baths. The section during the experiment to use the ice bath and hot water bath was difficult to see changes in color. If there was a way to detect the changes better and clearly, that would’ve been helpful. Temperature, size, opportunity to repeat the experiment – what about the color?

Real World Application:

There are vast uses for La Chatelier’s Principle. A few interesting examples the team discussed where in regards to hemoglobin and oxygen. As some people know, hemoglobin is the protein in red blood cells that is responsible for carrying oxygen. As long as there is sufficient oxygen, equilibrium is maintained. A shift could be seen in the equilibrium towards the left (away from oxygenated hemoglobin) at high altitudes. The way to balance this shift is pressurized oxygen from an oxygen tank. People that are born at higher altitudes or spend lots of time at higher altitudes can adjust to this change in pressure because the body itself produces more hemoglobin. Need citation

By comparison, team members also discussed what happens to equilibrium when hemoglobin is exposed to carbon monoxide. When hemoglobin binds to carbon monoxide, the bond is much stronger (about 300 times) than the bond of hemoglobin to oxygen. Because of this affinity the carbon monoxide bond takes precedence over the hemoglobin oxygen bond. The only way to treat this is to apply pure oxygen to the patient to help the equilibrium be reestablished. (Science Clarified, n.d). ok

Conclusion:

While all the students in Team D performed the experiment individually, at the end the team discussed the results, which were similar in Part Two but not in Part One. The members decided there needs to be able to detect color change during the water baths and discovered a couple real life applications this experiment could be useful to include changes that can affect the equilibrium of red blood cells. [Your paper will benefit from a stronger conclusion. A concluding paragraph summarizes the main idea, ties the main points together neatly for the reader, and ends with a sense of finality. Avoid introducing new ideas in the conclusion.]

General comment – pace was good and easy to read. A bit underdeveloped in the latter sections and missing link to theory. Missing research. Use three – these will give you more ideas.

Specific – I liked the formula for success – add a main theme – use the theme in the body and state the results as the main take away in the conclusion – these will get you there since the actual language is really good.

Use an insert page break

Reference

Science Clarified. (n.d). Homogeneous and Heterogeneous Equilibria. Retrieved from

http://http://www.scienceclarified.com/everyday/Real-Life-Chemistry-Vol-2/Chemical

Equilibrium-Real-life-applications.html

Written Assignment Feedback

Content/Development – 50%

Subject Matter : 30% (5% each) 26% development of the changes could be better

· Key elements of assignments covered – key elements are listed below:

Prepare for a discussion by individually reviewing the labs assigned in the previous week.

Discuss the lab and individual results as a team.

  Write a 350- to 700-word reflection of the team discussion.

  Include the following in your reflection:  

Briefly summarize the team discussion on individual results. Discuss and compare your responses to the end-of-lab questions. What kind of changes would you make, if any, if you were to do this lab again? expand Include a discussion of differences between the individual data sets. I would have liked more discussion What are the real-world applications of the labs?

· Content is comprehensive/accurate/persuasive

· Displays an understanding of relevant theory develop

· Major points supported by specific details/example

· Research is adequate/timely

· Writer has gone beyond textbook for resources need three

Higher-Order Thinking : 20% (10% each) 20%

· Writer compares/contrasts/integrates theory/subject matter with work environment/experience

· At an appropriate level, the writer analyzes and synthesizes theory/practice to develop new ideas and ways of conceptualizing and performing

Structure 50%

Organization 20% (4% each) 16% see comments in intro and conclusion – main theme

· The introduction provides a sufficient background on the topic and previews major points

· Central theme/purpose is immediately clear [Review this paper's thesis statement, introduction, and outline. You may want to use the Thesis Generator from the Center for Writing Excellence homepage. This is an easy-to-use online tool designed to aid in drafting a thesis statement and an outline for an essay.]

· Structure is clear, logical, and easy to follow

· Subsequent sections develop/support the central theme

· Conclusion/recommendations follow logically from the body of the paper

Style/Mechanics 30%

Format--10% 10% good

· Citations/reference page follow guidelines

· Properly cites ideas/info from other sources

· Paper is laid out effectively--uses, heading and other reader-friendly tools

· Paper is neat/shows attention to detail

Grammar/Punctuation/Spelling--10% (5% each) very good 10%

· Rules of grammar, usage, punctuation are followed

· Spelling is correct

Readability/Style--10%(2% each) 10%

· Sentences are complete, clear, and concise

· Sentences are well-constructed with consistently strong, varied structure

· Transitions between sentences/paragraphs/sections help maintain the flow of thought

· Words used are precise and unambiguous

· The tone is appropriate to the audience, content, and assignment

92% good work