Scientists and engineers record laboratory data in bound notebooks with pre-numbered 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, observations and an explanation of how your procedure was used to obtain the desired results.  The laboratory notes will be initialed by your instructor before you leave the lab and turned in with your typed laboratory report.

A.  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.  All qualitative observations made during the experiments should also be recorded in a data table.  Raw data and observations will always be recorded in a bound laboratory notebook.

Data will be recorded in blue or black ink, not pencil.  Errors can be lined out.

Your instructor may require you to obtain his initials on your data sheets prior to leaving the lab.

B.  Description of Procedure:  You should have an outline of the procedure you used and diagrams of the experimental procedure to refer to when writing the procedure section of your laboratory report.

FORMAL REPORT TYPED

I.  Title of Experiment (must be descriptive)

II. Introduction

A.  Research Question:  Define the problem in a concise and clear statement. This section of the report is a paragraph t hat discusses the objective or purpose of your investigation clearly and specifically.  It answers the question, “What problem was I given in this lab, and how do I intend to solve it?”  To assess Design in a lab, the teacher cannot give you detailed information and guidance.  Instead, you’ll be given a general, open-ended problem such as “Investigate the factors that affect X”.  You must do some thinking to recognize the nature of the problem that has been set, the factors (variables) that will affect the outcome, and how they affect it (the hypothesis).  So if a general question has been posed, make it more specific and relevant to your individual experiment.  Discuss how you intend to approach the problem.   Note:  If you simply paraphrase and repeat the problem as provided by the teacher, you get a "not at all" for this section!

B.  Hypothesis or Predicted outcome:  For many labs you will need to make a prediction instead of formulating a hypothesis.  If the lab question is not determining a relationship between two variables you will make a prediction instead of a hypothesis.  If 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.   You should support your prediction.   Explain the logic and chemical concepts used to make your prediction.  Write a hypothesis, describing the anticipated relationship between the independent and dependent variables.  A hypothesis should predict the outcome.  A hypothesis is like a prediction.  It will often take the form of a proposed relationship between two or more variables that can be tested by experiment:  “If X is done, then Y will occur.”   (Examples:  “The pressure of an ideal gas will be inversely proportional to its volume if the temperature is held constant” or “The rate of the reaction should increase if the temperature and/or the concentration are increased”).  You must also provide an explanation for your hypothesis.  This should be a brief discussion (in paragraph form) about the theory or “why” behind your hypothesis and prediction.  For example, why should raising the temperature of a reaction increase the rate?  Why does the pressure of the gas increase when the volume decreases?  (Notice that if you omit the explanation, you can only earn a score of “partial” on this second aspect).  Include balanced chemical equations if necessary to explain your hypothesis.   Explain the logic and chemical concepts used to develop your hypothesis or your expected results.

C.  Discussion of Variables and Expected Results:  Variables are those factors that might influence the outcome of the experiment.  You should identify and list all reasonable variables, and briefly state why each one is relevant.  Then identify which variable(s) is/are independent variables (ones that you will manipulate and change) and which are the dependent variables (the ones that will respond to what you did).  The remaining variables must be controlled.  If there is a control you should identify the control and describe the purpose of the control.

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

A.  Included a list of materials, equipment and chemicals used during the experiment.

B.  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.  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.

C.  Diagram the experimental set up.

IV. Data Collection and Presentation

A.  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.  All qualitative observations made during the experiments should also be recorded in a data table.

V:  Data Processing (the calculations and graphs do not need to be typed but must be included in the type report)

A.  Calculation Tables:  When performing calculations your work must be shown and units must be included.  Answers must be reported in the correct significant figures and included the uncertainty.  Organize calculations in clearly labeled tables. Identical, repetitive calculations do not have to be repeated.

B.  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.)

C.  Diagrams or drawings

VI. Conclusion and Evaluation:

A.  The conclusion is a discussion of how the lab data and experimental results demonstrates a particular chemical principle or reveals a relationship between variables.  Conclusions should be clearly related to the research question and purpose of lab.  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.  Interpret the data or observations in light of your hypothesis or your own expectations.

B.  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!]

C.  Identify and critique procedural mistakes that could have affected the data.  Discuss the agreement or disagreement between your expected results and the experimental results.  Show how you arrived at your uncertainty estimates and show the error propagation equation(s) you used.  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.

D. Tell how you would design the procedure and strategy to minimize uncertainties. Suggest real improvements (that can be carried out in the school lab) to the investigation.  Discuss further investigations that are of interest and can be carried out and new questions that could be posed.

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 in notebook are dated and numbered

9.      Pages cannot be removed from notebook

10.  Title and show all work for every calculations

11.   Report all data and derived values in significant figures

12.   Report uncertainties

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

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