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Description Objectives for Assessment post By completing this graded discussion post you will reinforce your understanding of several objectives of Module 2 (Measurement in Chemistry) Correctly report your answer to an arithmetic problem involving addition or subtraction Correctly report your answer to an arithmetic problem involving multiplication or division Correctly report an answer to a problem in which addition or subtraction and multiplication or division are mixed. INSTRUCTIONS Below you will find several arithmetic problems using measured values. Working through these problems will give you a chance to make sure you understand the rules of arithmetic with measured values. (Links to an external site.) Be sure to submit this discussion by 16 Dec. Instructions--Solve each problem on your calculator--you need not show individual steps but be sure to report your answer according to the rules. Remember that in addition/subtraction problems (Links to an external site.) you report your answer to the least degree of precision. On the other hand, in multiplication/division (Links to an external site.) problems you report your answer with the smallest number of significant figures in your problem. After you report each answer, give a one or two sentence explanation of why you reported your answer as you did. You might refer to Module 2 (Measurement in Chemistry) to help you with your explanations. You can refer to the rubric to see how the discussion post will be graded. SOLVE THE FOLLOWING PROBLEMS, REPORTING YOUR ANSWER PROPERLY 1. (34.56 cm) * (10.00 cm)*(4.95 cm) = _____________cm3 Explanation: 2. 56.79 cm + 1.458 cm + 116 cm = _____________cm Explanation 3. 3410 m + 89.54 m + 11,000 m = ____________m (Consider ambiguous zeros as non-significant) Explanation: 4. (123.54 cm - 121.91 cm) * (0.5487 cm) = _________________cm2 Explanation:

Description A. Place a plastic weighboat on the scale and tare (re-zero) the scale. B. Measure 1.0 g of the copper gluconate in the weighboat on the scale. If you don’t land exactly on 1.0, that’s OK. Just get as close as you can, and record the exact mass in Table 1 below. C. Transfer all of the copper gluconate into a glass 250 mL beaker. Try not to leave any behind in the weighboat, as this will affect your calculation later. D. Using a clean, dry 10 mL graduated cylinder (you may want to first rinse with distilled water prior to using, then dry), measure 10.0 mL of 0.5% NaCl solution, and pour it into the beaker with the copper gluconate. If you need to use a pipette to help transfer the NaCl into the graduated cylinder, that’s fine. You may need to gently swirl or stir (with your glass stirring rod) the solution if all the copper gluconate does not immediately suspend into the solution. E. Place 2 aluminum (Al) washers into the beaker with the solution. F. Fasten your iron ring to your ring stand, about 6-10 inches high. Place your beaker on the iron ring. It should fit just enough inside the ring where it won’t fall, but if yours does not fit as nicely as you’d like, you can place your watchglass over the ring to create a more stable platform on which to sit your beaker. Be very careful that your beaker does not fall, or you will lose your data for this experiment, not to mention have a mess to clean up. G. Place your Sterno® fuel underneath your beaker. This will be your heat source and take the place of a traditional Bunsen burner. Your final setup should look similar to this:

Description Solid Titanium metal (Ti) reacts with iodine gas to form solid Titanium(III) iodide. The balanced equation is: 2Ti (s) + 3I2(g) --> 2TiI3 (s) The heat of reaction for this is measured to be: delta H(rxn) = - 839 kJ. Answer the following questions in regards to the above process: (a) Is the reaction exothermic or endothermic? (b) What will be the enthalpy change for 25.00 g of iodine gas?

Description Please complete the lab report template exactly as stated by using all of the attachments provided. Experiment and date are included in the attachments. Thank you.

Description By using the attached links, this assignment requires you to answer analysis questions on solution concentrations and types of mixtures. Additionally, there are a few basic chemical math problems and it requires you to conduct a small experiments in order to identify solutions, colloids, and mixtures. All the links needed to complete the assignment are included below. Concentration Simulation Solution Suspension Colloid Osmosis and Water Potential Diffusion

Description the entire lab is attached in the file below please fill it out and return it as a PDF

Description Hello, please use all of the documents attached to complete the attached lab report template for Organic Chemistry lab. Thank you!

Description Despite the negative attention they often receive, fats (and other lipid molecules) play an extremely important role in the biochemical processes in our bodies. For this task, you will consider some of the biochemical roles of lipids (especially fatty acids) and demonstrate how a complete lack of fat in the diet would affect these biochemical roles and human health in general. You should compile your work for this task in a single document (e.g., Microsoft Word, Google Document) that includes diagrams, text explanations, and references. If a requirement asks for an explanation, you should provide a written response in a narrative style (i.e., complete sentences rather than bullet points). Note: Multimedia presentations (e.g., PowerPoint, Keynote) will not be accepted due to potential originality concerns. Note: Please save submission documents as *.doc, *.docx, *.rtf, or *.pdf files. If you are using Google Documents, you must save the file in *.pdf format and upload the *.pdf file. Scenario: You have been asked to help dietitians in a local community health center to better understand the importance of fat in the diet and particularly how no-fat diets affect the biochemical processes of the body. Requirements: A.  Explain how lipids, in the form of triglycerides, are broken down to produce ATP, including each of the following: ?  the pathways involved in the breakdown ?  the substrate(s) and end product(s) of the pathways B.  Explain two differences between saturated and unsaturated fatty acids (not fats). 1.  Create one original 3-D model to demonstrate the chemical structure of a saturated fatty acid. 2.  Create one original 3-D model to demonstrate the chemical structure of an unsaturated fatty acid. Note: Take a picture of your completed 3-D models as evidence that you created them. You can include the pictures as part of your document, or you can submit them in Taskstream as separate attachments. C.  Create an original diagram, with clear labels, to demonstrate the fluid mosaic structure of cell membranes. Note: The inclusion of the following components aids in demonstrating the fluid mosaic structure: phospholipids, hydrophilic portion, hydrophobic portion, and membrane protein(s). D.  Explain how no-fat diets can affect the body (e.g., nutrient absorption, essential fatty acids), including eachof the following: ?  the molecule, or class of molecules affected ?  how the absence of fat influences the availability of the molecule, or class of molecules ?  the consequence(s), at the biochemical level (i.e., not simply physiological changes), of the change in availability E.  When you use sources, include all in-text citations and references in APA format. Note: For definitions of terms commonly used in the rubric, see the Rubric Terms web link included in the Evaluation Procedures section. Note: When using sources to support ideas and elements in an assessment, the submission MUST include APA formatted in-text citations with a corresponding reference list for any direct quotes or paraphrasing. It is not necessary to list sources that were consulted if they have not been quoted or paraphrased in the text of the assessment.

Description Assignment: The Origin of the Elements The fusion of deuterium and tritium isotopes fuels the Sun. This reaction also explains the existence of helium in the Sun and other stars. But what about the other elements? How did heavier elements, like oxygen, nitrogen, and sulfur, first form? Are they still forming today? If so, where and how? To investigate these questions, you will journey into a star and carry out the two-part exploration outlined below. Click each tab to review the assignment. Part 1: The Elements: Forged in Stars Visit The Elements: Forged in Stars (http://unctv.pbslearningmedia.org/resource/ess05.sci.ess.eiu.fusion/the-elements-forged-in-stars/) and use the background essay and 3-minute video to find the answers to the following questions: How does a star glow? What types of elements are found in stars? What is a supernova? Why does it take so much heat and pressure to create helium and other elements? Part 2: Show What You Know Perform a Web search using terms, such as “stellar nucleosynthesis,” “helium burning,” “carbon burning” and “neon burning,” to locate balanced equations that show the fusion of lighter elements into heavier elements. Write balanced nuclear equations for the formation of five elements whose atomic number is between helium (2) and iron (26). Present your findings for your research for Part I and II in one of the following formats: a web page that will be accessed by middle school students learning about stars a slideshow presentation OR short video that will run at your local science museum in conjunction with an exhibition on the origins of the universe

Description Include the following information at the top of the first page of your assignment: Name: Lab Partner Name: Lab Section Number: Experiment Title: Due Date: GENERAL INSTRUCTIONS The entire report should be typed (handwritten portions will NOT be graded). Please organize your report as shown below. You and your lab partner may not work together on the data analysis, or turn in the same work or answers to questions. If you need help with calculations, you may ask for help from your instructor or the tutoring center. DATA & CALCULATIONS Part B: Show typed calculations for the following values: mhot, ?Thot, qhot, mcool, ?Tcool, qcool, qcal, ?Tcal, and Ccal. Create a table of just the calculated values listed above, displaying each value with proper units, mathematical sign and correct number of significant figures. Part C: Show one set of typed calculations for the following values: msoln, ?Tsoln, qsoln, qcal, qneut, mole of the limiting reactant and molar qneut. If you performed multiple trials, only show calculations for one trial. Create a table of just the calculated values listed above, displaying each value with proper units, mathematical sign and correct number of significant figures. If you performed more than one trial, report the values for all trials in this table, as well as the average molar qneut. QUESTIONS – All answers should be typed and given in complete sentences unless otherwise indicated. If some of the hot water evaporated during the heating process in part B, would that cause the calculated value of Ccal to be too large, too small, or unchanged in magnitude? Explain your reasoning. Write the chemical equation for the reaction in part C and give the molar heat of reaction. Based on the data, is the reaction in part C exothermic or endothermic? Explain your answer. As part of your answer, explicitly state from where and to where the heat flowed during the reaction. For each of the following components from part C, indicate whether they are part of the a. b. c. d. e. f. system or the surroundings. Styrofoam cups Thermometer Hydrochloric acid Sodium hydroxide Water from the sodium hydroxide solution Water product from the reaction 4. Give two possible sources for error that might have occurred during part C. Your answer cannot be based on just ‘human’ error (examples: calculation error, not following directions). Instead think about how the experimental set-up might lead to error.  DATA: Part B: 80 degrees C -hot water 59.3 degrees C -hot and cold water mixed 24.3 degrees C - cold water 45 mL styrofoam cup 80 mL heated beaker Part C: .996M HCl 1.10 M NaOH 51 mL NaOH @ 24.6 degrees C 46 mL HCl @25.5 degrees C NaOH and HCl mixed 31.4 degrees C