Chemistry lab homework help

Post Lab Assignment – Synthesis and Limiting Reactant CHEM 131L Spring 2016 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 turn in the same work. DATA & CALCULATIONS Useful Information: The 25.0 wt % ethylenediamine solution contains 25.0 % ethylenediamine by mass, dissolved in water, and has a density of 0.950 g/mL. First calculate the mass of the C 2H8N2 solution from its volume and density, then calculate the mass of the C 2H8N2 by remembering that From their masses and formula weights, you should then compute the number of moles of NiCl 2•6H 2O and of C 2H8N2 that were used. (Remember the formula weight of NiCl 2•6H 2O should include the mass of the waters of hydration.) 1. Create a typed table that co ncisely presents the quantities (mass or volume as appropriate for each reagent, as well as mol es for all reagents ) and appearance of both of the reactants and the nickel product . (Remember to clearly label the table with a title and headers for all data columns/ rows. Avoid blank cells in the table.) 2. What was the limiting reactant for your synthesis? Show your typed calculations. 3. What was the theoretical and percent yield of trisethylenediaminenickel(II) chloride for your experiment? Show your typed ca lculations. 4. Assuming all of the limiting reactant was completely consumed (reacted), how many moles of the other reactant (non -limiting) remained? Show your typed calculations. mass of solute wt % solution = x 100 mass of solution QUESTIONS – All answers should be typed and answered in complete sentences. 1. What was the purpose of cooling the reaction mixture in an ice -water bath? Support your answer with what you observed during th is step of the synthesis. 2. Suggest at least one reason why a percent yield of less 100% would be obtained . Use an actual observation from this experiment to support your answer. 3. During the purification of compound step, what would you expect to happen to the percent yield of the product if a student washed the product with water rather than acetone? Explain your answer. 4. During the purification of compound step, what would you expect to happen to the percent yield of the product if a student only dried the product for 1 minute ? Explain your answer. ADDITIONAL PROBLEM 1. Consider the reaction: Mn O2 (s) + 4 HCl (g )  Mn Cl 2 (s) + Cl 2 (g) + 2 H 2O (g) If 1 0.00 g of MnO 2 and 1 0.00 g of HCl are reacted, how many grams of Mn Cl 2 can be produced? Show all calculations.