Laboratory Manual for Chemistry 102
Total Page：16
File Type：pdf, Size：1020Kb
LABORATORY MANUAL FOR CHEMISTRY 102 Prepared by Department of Chemistry and Physics Los Angeles Valley College This Lab Book Belongs To: Copyright © 2017 by the Department of Chemistry and Physics, Los Angeles Valley College. All rights reserved. No part of this publication may be reproduced or distributed in any form or by any means, electronic or otherwise, or stored in a database or retrieval system, without written permission of the copyright holder. 2 TABLE OF CONTENTS Contents LABORATORY SAFETY RULES ....................................................................................................... 3 LAB NOTEBOOK ................................................................................................................................ 7 Ksp, G, H, AND S OF POTASSIUM NITRATE DISSOLVING IN WATER ....................... 9 LE CHÂTELIER'S PRINCIPLE ....................................................................................................... 15 WEAK ACIDS AND BASES .............................................................................................................. 23 DETERMINATION OF Ka BY pH TITRATION ............................................................................ 30 BUFFERS AND pH ........................................................................................................................... 39 ACID-BASE EQUILIBRIUM PROBLEMS ..................................................................................... 43 A SOLUBILITY INVESTIGATION ................................................................................................. 48 SOLUBILITY AND Ksp DETERMINATION .................................................................................. 52 DETERMINATION OF Kf BY SPECTROPHOTOMETRIC METHODS .................................... 56 DETERMINATION OF PERCENT OXALATE BY OXIDATION-REDUCTION TITRATION 61 ELECTROCHEMISTRY ................................................................................................................... 67 ELECTROLYTIC DETERMINATION OF THE MOLAR MASS OF LEAD ............................... 76 FACTORS AFFECTING THE RATE OF A REACTION ............................................................... 79 CHEMICAL KINETICS .................................................................................................................... 84 DETERMINATION OF THE HALF-LIFE OF POTASSIUM-40 ................................................. 91 EQUILIBRIUM BETWEEN TWO COMPLEX IONS OF Co2+ IN SOLUTION ......................... 96 SYNTHESIS AND ANALYSIS OF A NICKEL COMPLEX ......................................................... 104 MOLECULAR MODELS OF TRANSITION METAL COMPLEXES ........................................ 110 CHECK OUT INSTRUCTIONS ..................................................................................................... 114 APPENDIX A ................................................................................................................................... 116 APPENDIX B ................................................................................................................................... 117 APPENDIX C ................................................................................................................................... 127 3 LABORATORY SAFETY RULES Note: Failure to follow safety rules will result in expulsion from this course. 1. Wear approved safety goggles at all times in the laboratory. 2. It is not advisable to wear contact lenses during lab. 3. Do not wear loose clothing to lab. It is a fire hazard. 4. Tie back long hair. It too is a fire hazard. 5. Wear closed shoes to lab. 6. Never put anything into your mouth while in the lab. 7. Immediately wash off any chemicals spilled on your skin or clothes. 8. Keep the lab neat. Return reagent containers and equipment to proper locations. Put any belongings not needed for experimental work on the shelves provided. 9. Clean up all chemical spills or broken glass immediately. 10. Think about how much chemical you will need before you take it from a stock (reagent) bottle. Never return unused chemicals to stock bottles. Never dip into a reagent bottle with anything (spatula, dropper, pipet, etc.)! 11. Dispose of waste chemicals only as instructed. 12. Behave in a responsible manner. 13. You should be aware of the location and use of laboratory safety equipment. 14. Immediately report accidents and injuries to your professor. 15. Do not perform unauthorized experiments. 16. Thoroughly wash your hands any time you leave the lab. 17. No smoking on the Los Angeles Valley College campus. I have carefully read all of the safety precautions summarized above and recognize that it is my responsibility to observe them throughout this course. Chemistry 102 Printed Name Date Section Number Signature 4 5 LABORATORY SAFETY RULES Note: Failure to follow safety rules will result in expulsion from this course. 1. Wear approved safety goggles at all times in the laboratory. 2. It is not advisable to wear contact lenses during lab. 3. Do not wear loose clothing to lab. It is a fire hazard. 4. Tie back long hair. It too is a fire hazard. 5. Wear closed shoes to lab. 6. Never put anything into your mouth while in the lab. 7. Immediately wash off any chemicals spilled on your skin or clothes. 8. Keep the lab neat. Return reagent containers and equipment to proper locations. Put any belongings not needed for experimental work on the shelves provided. 9. Clean up all chemical spills or broken glass immediately. 10. Think about how much chemical you will need before you take it from a stock (reagent) bottle. Never return unused chemicals to stock bottles. Never dip into a reagent bottle with anything (spatula, dropper, pipet, etc.)! 11. Dispose of waste chemicals only as instructed. 12. Behave in a responsible manner. 13. You should be aware of the location and use of laboratory safety equipment. 14. Immediately report accidents and injuries to your professor. 15. Do not perform unauthorized experiments. 16. Thoroughly wash your hands any time you leave the lab. 17. No smoking on the Los Angeles Valley College campus. Come to lab prepared!! Carefully read the experiment before coming to lab. 6 Quantity Description 2 Beaker, 20 mL 2 Beaker, 50 mL 2 Beaker, 100 mL 2 Beaker, 150 mL 2 Beaker, 250 mL 1 Beaker, 400 mL 1 Beaker, 600 mL 1 Bottle, 500 mL, Screw Cap 1 Bulb, Pipet 1 Clamp, Buret 1 Cylinder, Graduated, 10 mL 1 Cylinder, Graduated, 50 mL 3 Flask, Erlenmeyer, 250 mL 1 Forceps 1 Funnel, Small, 45 mm 1 Holder, Test Tube 1 Microspatula 1 Pipet, Graduated 1.0 mL 2 Pipet, Graduated 5.0 mL or 10.0 mL 1 Pipet, Volumetric 10 mL 1 Pipet, Volumetric 25 mL 2 Rack, Test tube 4 Shell Vials 10 Test Tube, 10 mm x 75 mm 10 Test Tube, 13 mm x 100 mm 1 Test Tube Brush, 12 mm x 62 mm 1 Thermometer, -20°C to 110°C 1 Tongs 1 Wash Bottle, Polyethylene, 250 mL 1 Watch Glass, 75 mm 7 LAB NOTEBOOK A record of all experiments you perform in the laboratory will be kept in a notebook that is bound and has page numbers. This laboratory notebook is as important as the actual experiments you perform and constitutes a permanent record of your experimentation. Therefore, all entries are to be made in ink, and mistakes are to be crossed out with a single line (no white out, no erasures). Use the first page of your notebook as table of contents that is kept up-to-date. An experiment should always be started on a new page of the notebook. If you have to start another experiment before finishing the previous one, leave 2 or 3 extra pages at the end of the experiment, so that all of the work for a given experiment will be on consecutive pages. All work should be done in the notebook and not on separate sheets of loose paper. For example, additional questions or mechanisms that you are asked to address in the discussion should still be included in the notebook after the results section. Use professional language throughout the notebook; avoid first and second person pronouns like I, my, you, etc. You should number, sign and date all pages of an experiment. Each experiment should have the following format: I. Title II. Purpose: A brief yet complete summary of the goals of the lab. In the context of these goals, briefly mention which basic techniques are to be used and the role that those techniques serve (for example, "isolated by extraction, purified by distillation, and analyzed by GC"). It takes practice to write a good purpose statement. You may want to leave a blank space and write the purpose after you completed sections III-VI, to ensure that you really understand why a particular experiment is being done. III. Balanced reaction(s): Use line structures or Lewis structures, not abbreviations; do not include mechanisms; do include possible side reactions; where necessary. IV. References V. Table of reagents and products: List all chemicals (name and structure) to be encountered in this experiment – all reactants, reagents, solvents, and products. Include molecular weights and relevant physical properties (e.g. mp, bp, density, solubility, concentration) for all entries. Note: An incredibly useful website for finding data for various compounds is chemfinder.com. You are encouraged to register and use it! compound name and structure MW other properties VI. Procedure: Start writing the procedure on a new page of the notebook. The stepwise listing of operations is to be written Procedure D ata and O bservations using the left column of a page. In general it is a good idea to 1. To 1-butyl alcohol