LAB REPORTS FOR ORGANIC CHEMISTRY
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Lab reports submitted for grading must be typed or legibly written (in pen) on standard size
(8½ × 11") sheets, stapled (preferred) or bound in a small folder, and single sided.
Reports which are not stapled or bound will be penalized (-½ mark). 5% bonus for typed reports.
Attach your rough work pages from the lab to your final report.
Please Include all of the following 7 sections in your lab report and title them as shown:
1.
Experiment #
Title
your Name (& partner)
Date (performed)
2.
Object: 1-2 sentences stating the purpose of the experiment.
3.
Introduction: The student may need to refer to several literature sources, e.g., CRC Handbook,
Merck Index, Organic Chem/Lab books.
 1-2 sentences stating the sequence of operations employed in the procedure.
 Concisely explain the theory applicable to the procedure, e.g., melting point, distillation,
extraction, crystallization, etc.
 Write balanced chemical equations for the reactions. Calculate pKeq and extent of reaction
(%) for acid/base reactions whenever possible. Show the reaction mechanism by "pushing
electrons" and state the type of reaction, e.g., reduction, oxidation, elimination, etc. and give
reasons for reactions conditions, e.g., catalysts, heating, vacuum, reflux, etc.
 Briefly explain the principle of operation of any instruments used for analysis, e.g.,
refractometer, UV, IR, GC, etc.
 Draw up a "Table of Physical Constants" for all reagents and solvents used in the
experiment. Include the following: 1] Compound names, formulas, and structures 2] MW
(g/mol), 3] mp. (C), 4] bp. (C), 5] , 6] Characteristics & Solubilities, 7] Other data if
it is relevant to a particular experiment, e.g. pKa or pKb.
Some of this data should be obtained before you begin the lab work, e.g., b.p. of product
4. Method: A concise outline of the steps taken including the weight of the starting materials. If a volume is
employed, convert the volume to the mass and place in brackets, e.g., 6.5 mL (6.9 g) cyclohexanol..
5. Data and Results: All pertinent information should be shown here...
 e.g., sample & standard weights, volumes, dilution factors, mp. (measured & theoretical)
 Graphs are inserted in this section. Use graph paper and include titles, axes labels & units.
Instrument printouts are also inserted here.
 For reporting several values of similar data, use ruled tables. Note that in tables, units are written
only once at the top of each column or to the left of each row in the table.
If a table is too wide for your page, rearrange the table to read vertically rather than horizontally.
 Sample Calculations should be included in the Data & Results section. Unless othewise directed,
record all results of all trials but only show one example of each type of calculation in this section.
Show the calculation of % yield by placing the masses used and recovered below the balanced
equation and manipulate accordingly. You may need to determine the yield-limiting reagent to
calculate your yield.
6. Discussion:
 Discuss the accuracy & precision of results. Report % error and % recovery when possible.
 Give the reasons for using specific techniques, e.g., salting out, distillation, extraction.
 Compare industrial vs. laboratory methods of synthesis or purification.
 List practical applications/uses of the main chemical compounds used/produced in the lab.
7. References: Include a bibliography of literature sources used. It is not necessary to reference
handbooks such as the CRC or Merk Index re: physical property data.
Example of a Reference: (note that the title is underlined)
1. Day, R. A., Underwood, L. A., Quantitative Analysis, A Lab Manual, 2nd ed. Prentice Hall Co.,
Toronto, Canada, (1970).
Writing Style For Lab Reports:
 Grammar and spelling are graded. Write in complete sentences and use a dictionary (or spell-check)
to check your spelling.
 Whenever it is necessary to describe procedures that were followed, write in the “past passive”
tense. Do not use pronouns and do not write in the “imperative”, i.e., no commands.
1. Correct... “The sample was heated...”
Incorrect... “We heated the sample...”
(don’t use pronouns)
Incorrect... “Heat the sample...”
(don't use an imperative form of the verb)
2. Correct... “A 25 mL portion was mixed with...”
Incorrect.. “We mixed a 25 mL portion with...”
Incorrect.. “Mix a 25 mL portion with..”
Example of Explaining and Applying Theory:
Say for example, a non volatile solute (e.g., sucrose) is to be separated from a volatile solvent (e.g.,
water) by simple distillation, a student would explain and apply the theory as follows.
The boiling point of a substance is the the temperature at which its vapor pressure is equal to
atmospheric pressure. At this temperature, vapor bubbles form in the liquid and ‘boil out’ as a
gas. Distillation is the process of heating a liquid to its boiling point, passing its vapors into a
cooling device called a condenser, and collecting the liquid condensate. When the boiling
points of two components are very different (e.g., greater than 40Cº difference) a simple
distillation is sufficient to separate the components, i.e., a fractionating column is unnecessary.
In our experiment, sucrose is a nonvolatile solute in a volatile solvent, water. Sucrose (a solid,
decomposing above 150ºC) has no vapor pressure, so it will not codistill with the water during
simple distillation.
According to Raoult’s Law, a nonvolatile, nonionizing solute (such as sucrose) will lower the
vapor pressure of a solvent. Mathematically this is expressed as Psolvent = xsolvent Po, where x is
the mole fraction of the solvent and Po is the vapor pressure of the pure solvent. As a result,
aqueous sugar solutions, like the one in our experiment, having lowered vapor pressure, will
boil at temperatures above the normal boiling point of water. In our experiment, the sucrose
solution began to boil at 102ºC and this rose to 104ºC during distillation as the mole fraction of
the sucrose increased during the distillation.
LAB REPORTS FOR ORGANIC CHEMISTRY
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Lab Procedures and Rules:
1. Be prepared for each lab. Read over the experiment and necessary theory in advance.
2. At the start of each lab, the instructor will provide a brief overview of what is required and answer
any questions. Arrive on time. Do not miss the prelab.
3. Failure to wear safety glasses will result in ... 1st infraction = -1mark, 2nd = -2, 3rd = “-3, etc.
4. Lab coats must be worn required during labs, long hair tied back and no open shoes allowed.
5. Keep your work area free of unnecessary stuff, i.e., winter coats, nap sacks, etc. and keep your
locker doors closed whenever possible to ensure an open walkway.
6. At the end of each lab session:
 put all equipment and reagents away (in the correct labelled cupboards)
 dispose of waste solvents in designated waste containers. Use the 2 sinks at ends of the lab
to dispose of non hazardous wastes. (Ask your instructor if you are unsure). Put no waste
of any kind down the central drains (troughs). These drains are for water only, e.g., cooling
water from a condenser.
7. During or after use, Pasteur pipets should be placed upright in a beaker, test tube, or other suitable
container. They must not be laid down in the fumehood or on your bench top or they will leak
the liquids they contain. A 1-mark deduction will be assessed for each violation of this rule.
Dispose of Pasteur pipets in the designated beaker in the sinks after rinsing.
8. Any broken glass must be swept up and brought to the stockroom - not in the garbage can.
9. Use a wet paper towel and wipe down your work areas (bench top, fumehood, sink, etc.).
Failure to clean up behind yourself will cost you 1 mark per time on the lab report.
10. Submit lab reports on scheduled due dates. Overdue lab reports be penalized 20% per school day.
LAB REPORTS FOR ORGANIC CHEMISTRY
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