Scientists and engineers record laboratory data in bound notebooks with pre-numbered and dated pages. These books serve as a permanent record of the work, and can serve as legal evidence in priority disputes. Many colleges and universities will want to see your lab notebook and lab reports when deciding whether or not to give you college credit for your high school class - Regardless of your AP/IB test scores.  The first two pages of your laboratory notebook will be used for a table of contents.  For each laboratory experiment you will turn in laboratory notebook containing your lab notes and a typed lab report.  Each laboratory experiment will have two written records.

1. Laboratory notes kept in your laboratory notebook

2. Formal typed laboratory report

LABORATORY NOTES

Your laboratory notes reflect your personal style, but you should write it so that a co-worker familiar with the subject of your investigation could follow and understand what you have done.  You may need to refer to your notes at some later date, therefore you should include any and all information you may need to understand what you did, why you did it, and what results you got.  You should have an outline of the procedure you used, a data table, sketch of experimental set up, observations and an explanation of how your procedure was used to obtain the desired results.

FORMAL REPORT

Title of Experiment (must be descriptive)

I. Introduction

A.    Purpose or Hypothesis   Write a hypothesis, describing the anticipated relationship between the independent and dependent variables.  If the purpose is to identify a substance or to determine a property of a substance, using your knowledge make a prediction concerning the results.  If a relationship between variables is not the subject of the investigation, but instead you are identifying a property of a substance or identifying an unknown you will need to clearly state the possible outcomes but may not be able to predict a result.  A short description of the problem being investigated or the specific question you are trying to test. Give a clear and specific statement of your aim for the experiment. If a general question has already been suggested, do not simply restate the question, but more it more specific and relevant to your individual experiment.

B.  Variables:  If a relationship is investigated identify the independent and dependent variables for the experiment.  If there is a control you should identify the control and describe the purpose of the control.

C.  Discussion of Chemical Principles Explored:  Briefly explain the logic and chemical concepts used to develop your hypothesis or your expected results.  In addition to describing the concepts explored, discuss all the background information, such as, chemical reactions, laboratory techniques or relationships required to obtain the results and analyze the data.  If a relationship between variables is not the subject of the investigation, but instead you are identifying a property of a substance or identifying an unknown you will need to describe how the procedure will provide the information required to identify the substance or used to determine the property of the substance.

II. Procedure (you will refer to your Lab notes to write this section)

A.  Materials:  Included a list of materials, equipment and chemicals used during the experiment.  Diagrams of experimental setups should be included when appropriate.

B.  Procedure:  In narrative form describe how you gathered your data.  It should be written in past tense.  Explain how you made sure that the sufficient relevant data was recorded.  Describe the method for data collection including measurements that were made the number of trials.

C.  Variables:  In this part you should explain the different variables unless the laboratory experiment is only an observation activity.  Describe how the independent variable was varied, how changes of the dependent variable were monitored and if the experiment contained a control how the control was maintained.

III. Data  Table

Data Table: (measurement must include units always) Record all your raw data in tables.  The tables should be numbered and have captions in which you briefly describe the contents of the tables and how you recorded the results.  Titles, units and the uncertainty should be given in the headings of the tables.  Underneath the table briefly describe the results. You can describe the main trends and account for any anomalous result.

IV. Results and Analysis

A.  Sample calculations:  A sample calculation for every required calculation must be included.  Your sample calculation should included : a descriptive title, the relationship used clearly written, the variables rearranged to show the algebra, units and numbers plugged into the relationship and the answer including units provided.

B.  Calculation Tables:  When performing calculations a sample of the work must be shown and units must be included.  Organize calculations in clearly labeled tables.

C.  Graphs:  If you use graphs, they should have a caption in which you describe the contents of the graph.  The axes of the graphs have to be labelled (ALL graphs are titled / each axis is labeled with what is measured and unit used for example: Time, sec.)

D.  Error propagation:

1.  Uncertainty:  Show how you arrived at your uncertainty estimates.

2.  Error Propagation:  Show the error propagation equation(s) you used.

V. Conclusion and Evaluation:

A.  Conclusion:  The conclusion is a discussion of how the lab data and experimental results demonstrates a particular chemical principle or reveals a relationship between variables.  State the outcome of the experiment in narrative form.  Explain your data.  Describe what it means and what it illustrates.  Identify and describe any relevant patterns within the data.   The methods of science never prove anything.  The conclusion must be justified using a reasonable interpretation of the data.

B.  Evaluate Procedures:  Identify and critique procedural mistakes that could have affected the data.  Discuss the agreement or disagreement between your expected results and the experimental results.  Error propagation equations motivate decisions about experimental design and procedures.  They also justify the uncertainties you assign to results.  If some error sources dominate others, this fact may deserve comment.  If the results do not make sense, examine your methods and materials for sources of experimental error, and describe how the error affected the results.  Evaluate the method used and identify main weakness in the procedure or methods of measurement, as well as, weakness in the manipulation of data.  Tell how the procedure was designed to minimize uncertainties.  Suggest real improvements (that can be carried out in the school lab) to the investigation.

C.  Compare to Literature:  Compare your results with literature values if possible.  Make meaningful comparisons where appropriate. When the experiment has numeric results which you can compare with other independent sources (from the literature for example) comment on that comparison.  Do not call this comparison the “error”, but rather call it the “experimental discrepancy”.  When you can quote both error and discrepancy, do so, and comment on their relative size. [An experimental discrepancy larger than the error discrepancy certainly requires some comment!]

D.  Questions:  Include the answer to all conclusion questions.  You do not need to write the question but you will need to number each question.

REMEMBER:

1.      Use a bound or spiral quadrille ruled notebook for laboratory notes.

2.      Laboratory  reports must be typed

3.      Use ink only for laboratory notes except for sketch of your laboratory set-up

4.      A sketch in pencil of your laboratory set-up must be included in your laboratory report

5.      Cross out mistakes in your laboratory notes with a single line only (you may need to retrieve this info.)

6.      All measurements must include a unit

7.      Graphs are titled and axis labeled

8.      All pages laboratory note bound book are dated and numbered

9.      Title and show a sample calculation for each required calculation

10.   Report all data and derived values in significant figures

11.   Report uncertainties

12.   Show how you arrived at your uncertainty estimates and show the error propagation equation(s) you used.

13.   In your discussion discuss your data and refer to the literature to compare your results to expected or accepted results.  Make suggestions for improvements.