CHEM 24112 Chapter Notes - Chapter 2: Significant Figures, Scientific Notation

General instructions: You must show full/detailed calculations to receive full marks for each problem. Please show your FINAL answer to correct number of significant figures. During intermediate steps, keep all digits in your calculator to avoid large rounding errors in the final answer. In other words, do not round off your answers during intermediate calculation steps. Use Ksp values from textbook – Harris 8th or 9th edition 1. A mixture having a volume of 10.00 mL and containing 0.1000 M Ag* and 0.04500 M Hg22* was titrated with 0.0800 M KCN to precipitate Hg2(CN)2 and AgCN. (b) (5 marks) At the first equivalence point in the above titration, will the second precipitate already start to form? Explain why or why not and show your calculation to derive the answer. (i) (2 marks) Can you propose a better titrant to perform this titration? Justify your reasoning briefly.

General instructions: You must show full/detailed calculations to receive full marks for each problem. Please show your FINAL answer to correct number of significant figures. During intermediate steps, keep all digits in your calculator to avoid large rounding errors in the final answer. In other words, do not round off your answers during intermediate calculation steps. Use Ksp values from textbook - Harris 8th or 9th edition 1. A mixture having a volume of 10.00 mL and containing 0.1000 M Ag' and 0.04500 M Hg22 was titrated with 0.0800 M KCN to precipitate Hg2(CN)2 and AgCN. (a) (3 marks) Explain which salt will precipitate first and why. b) (3 marks) Calculate volume of KCN required to reach first and second equivalence points and sketch by hand the expected titration curve. (c) (3 marks) Calculate pCN at 8.00 mL KCN added (d) (4 marks) Calculate pCN at 12.50 mL KCN added (e) (4 marks) Calculate pCN at 18.00 mL KCN added

Lab 6: Stoichiometric Analysis of an Antacid Andrewsky (adapted from Lucas and Ansell) CHEM&12 COMPLETING THE REPORT Work the pre-lab questions before your lab day. Your instructor will check in class that these questions have been done. in the lab, be sure that all data is recorded by each member of a lab team so that ill have the necessary information to complete the calculations later. After performing the experiment, complete the calculation sections by providing the results indicated. Show work for each result in the space available or attach additional pages in needed, and include all unit labels. Be careful to follow the significant figure conventions as you round off the results of calculations to the appropriate decimas place POST-LAB QUESTIONS Guidelines" for more information on responding to post-lab discussion questions. 1. (4 pts) In Part B, suppose the tablet was mostly dissolved when some of your solution splashed out of Use complete sentences in this section. Cite your lab data where appropriate. See the "Laboratory the beaker as CO; continued to evolve. How would this affect the perceived mass of CO? Would your final calculated mass of sodium bicarbonate in the tablet be artificially high or artificially low as a result of this splashing? Choose one, and explain why. TO TURN IN You will turn in this handout with all of the data, calculations, and responses to post-lab questions recorded on this handout. Staple your Purpose Statement and Procedural Outline to the back of this lab handout as well as any additional pages you completed work on. If additional pages were necessary, write a note within the handout to direct the instructor to find this additional work on these scrap pages