t s THE LABORATORY NOTEBOOK

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1 THE LABORATORY NOTEBOOK The laboratory notebook is a legal document describing ones activities as they apply to a given research project and, It is a teaching tool, to be used to remind or inform one of the methods and procedures used while conducting research. The Laboratory Notebook should: 1. Be sewn-bound and contain permanent, numbered pages Loose-leaf ring binders and spiral notebooks are inappropriate, since pages can be easily removed or lost. Never remove pages from the notebook. Some notebooks may have duplicate pages that may be removed and submitted as part of a laboratory report. If errors are made, draw a line through them or X-out the error, sign and date the entry.. Lab Notebooks contain a Table of Contents Set aside the first two or three pages for this function.. Begin each new experiment on a new page. 4. X-out unused or invalid sections of the notebook 5. Complete experiments, pages and sections by signing and dating the section or page. 6. Sign and Date top of page to open new experiment. 7. Record all data and information in non-water based permanent ink. 8. To minimize disorganized presentations, adequately plan experimental procedures and operations before coming to the lab. a. Read and outline experimental background and procedures. b. Construct a flow chart or listing of procedures that you can easily follow during operation of the lab. c. Construct data tables with respect to established objectives. d. Transfer this information into your lab notebook while waiting for reaction to complete or at completion of experiment. 9. Have a general, easy to follow organizational format. One such format is a. Title (Purpose for single objective experiment) b. Purpose (if multiple objectives exist in single project) To examine the statistical Accuracy and Precision associated with a set of data collected in the same way. c. Background: i. Define the objective of your study. Accuracy and Precision are used to determine the experimental credibility of a study. Accuracy is the variation of data about an accepted value and is defined as percent error and is calculated via the following equation: Percent Error = Average Value Accepted Value Accepted Value X 100% Precision is the variation of data about an average and is defined by linear regression analysis. Linear regression Standard Deviation, Experimental Confidence Interval, and the Range of Reliability. The following equations are used to define each of these quantities. Standard Deviation (S): s m ( mi m) n 1 Confidence Interval (CI): ( CI) m t s n Range of Reliability (RR): (RR) = Average ± CI

2 The results of a linear regression analysis are generally interpreted as follows: If the accepted value falls within the range of reliability then the methods used to determine the average are considered reliable and can be used to determine other objective values. However, if the accepted value falls outside to the Confidence Interval, then the experimental methods used need refining in order to improve the precision of the experimental results. In this experiment, the accuracy and precision of experimental density data will be determine an analyzed by linear regression. Analysis and development of the method will be based upon calculation of several density values for CO (g). Density is a physical property of matter and is defined as mass per unit volume; or, D = Mass / Volume. The mass and volume values of a substance ( Carbon Dioxide ( CO ) will be determined multiple times and a set of density values calculated and analyzed by linear regression. ii. What have others done on the topic of interest? Review the literature pertaining to your topic. Theory, practical experiments, results obtained by others, etc. iii. Why are you doing this project? This project focuses is on development of a statistical method for analyzing a set of data points all collected in the same way. iv. How are you going to do the project? CO (g) will be generated via the following metathesis reaction: Na-Bicarbonate + Water Na-Carbonate + Water + CO (g) The mass and volume of CO gas will be collected and used to calculate density values. Using g/l as the accepted value and the calculated average of several experimental density determinations, %Error, Standard Deviation, Confidence Interval and Range of reliability will be calculated. v. Why do you think your method will work? Percent Error and Linear Regression Analysis have long been the standard methods of analysis for defining credibility of experimental methods. vi. What do you expect from experiment? The method of analysis developed in this experiment will be used in future experiments to assess the credibility one s experimental data collection and determine the validity of the overall experimental process. d. Procedure i. Should be based on objectives and background. ii. Should contain reaction equation(s) and quantitative information as it pertains to experiment. iii. Make notes while studying text and then construct a flow chart or listing of steps to follow while working in the lab. e. Cautions (Chemicals and Procedures) i. Chemicals refer to MSDS Documents (Material Safety Data Sheets for chemicals used) ii. Procedures list any operational hazards and note safety procedures and methods. f. Data and Observations i. Construct data table with respect to procedures outlined in previous section. It should be clearly labeled with sectional titles, headings, units and quantities be studied. ii. It should receive data in a logical sequence with respect to the procedures and operational methods being used.

3 g. Calculations i. Should contain at least one detailed calculation for each type of computation. ii. If repetitive calculations are being done, only one detailed calculation will be required as all others of the section will be the same except for the numbers being substituted. h. Analytical Analysis should contain: i. Graphs, Charts &Tables ii. All graphs, Charts, and Tables need Title What the Illustration is defining Labels on Graph Axis - including dimensional units Use a strait-edge to draw graphs that are to be straight lines. i. Conclusions Conclusions should focus on objective results. For example, Using the experiment Determination of CO (g) Density, the primary objective is to determine and analyze 5 trials for CO (g) density. The density of CO (g) was found to be.0 ± g/l, giving a Range of Reliability of [1.95g/L.094g/L] at a 99% t-factor and 4 degrees of freedom. The average value of density was found to be 6.% above the accepted value of 1.79g/L but, did fall within the Range of Reliability. This indicates the procedures used for this density analysis are adequate for density determinations for other gas phase substances produced by metathesis reactions and measured in the same way. NOTE: The above comments are the results of the specific objective results. The experimental values obtained are compared to an accepted value (% Error Analysis) and an average of the test results. The section DOES NOT contain personal recommendations or theories as to why the data trends occurred as they did. j. Discussions Should focus on those factors that most affected the experimental results and the recommendations and/or suggestions one could offer. This includes personal opinions as to how one could overcome certain problems; improve data collection accuracy and experimental efficiency. For example: The accuracy and precision of this experiment depends upon measurement of mass and volume values of gases generated by the metathesis reaction defined in the background section. Due to the small change in gas weight, measurements should be carefully determined to a 4-place accuracy using an analytical balance. Consistency in gas weight determination also depends upon one keeping the exterior of the experimental apparatus dry at all times. Volume determinations require that one completely displace all air from the gas receiving vessel ( in this case, a 100-mL graduated cylinder ) by carefully laying the cylinder on its side in the pneumatic trough so that the water will completely displace all air from the tube. 10. The experiment should have an Abstract Summary The Abstract Summary: For publications, the Abstract Summary is usually inserted immediately after the title of the experiment. For this lab program, the Abstract Summary will be inserted at the end of the experiment, set part from the ending section and clearly labeled. The abstract is a one or two paragraph summary of your experiment. It should answer the following in one or two sentences for each question. o What did you do in the experiment? o How did you do it? o What specific results did you obtain? o How do your results compare with standard or average data trends?

4 CHEM 4 / LAB QUIZ / PAGE 1 OF NAME IDENTIFY TWO MAJOR FUNCTIONS OF THE LABORATORY NOTEBOOK. NAME 9 ESSENTIAL ELEMENTS OF THE LABORATORY NOTEBOOK WHEN WRITING ONES BACKGROUND SUMMARY, WHAT 5 GENERIC QUESTIONS NEED BE ANSWERED? WHAT SPECIFIC SET OF DOCUMENTS (BOOKS) SHOULD ONE REVIEW FOR INFORMATION ON THE NATURE, HANDLING AND SAFETY OF CHEMICALS USED IN THE EXPERIMENT? CHEM 4 / LAB QUIZ / PAGE OF NAME WHEN WRITING ONES ABSTRACT SUMMARY, WHAT 5 GENERIC QUESTIONS NEED BE ANSWERED?

5 1 4 5 WHAT ESSENTIAL ELEMENTS NEED BE IN A TABLE, CHART OR GRAPH? 1