Administrator 123 Name Sample 123 By Administrator Date Wednesday, August 31 2016 Description 4000 600350030002500200015001000 129 57 60 65 70 75 80 85 90 95 100 105 110 115 120 125 cm-1 %T 3058.6 2968.2 2873.9 2826.7 2724.5 1702.5 Guidelines for Written Reports for Chemistry Labs at LU All lab reports will be submitted to Turn-It-In through Blackboard. Format: The report must be a typed electronic document, with reasonable margins and should be double spaced with 12pt. font. The report should be written in 3rd person past tense. (“A 20 mL portion of water was dispensed into a beaker.” not “I took the beaker and dispensed 20 mL of water.”) The report should include the following components: · Title Section – This section should include the title of the experiment, the name of the student author, full names of experimental partners, and the class and section. · Introduction – This section should include a very brief overview of the chemistry/theory involved in the lab. · History or Background – the report should contain some simple history or background about the experiment representing a context for why the experiment matters to the experimenter. (1-2 paragraphs) · Theory – The theory should describe the question that you are trying to answer with this experiment, or the underlying principle of the experiment. There may be more reactions or formulae that are the basis for the theory. (1-4 paragraphs) · Experimental Method – This should be the most detailed section of the lab report. · Hazards or Warnings (if applicable) – experimental dangers should be noted here and should be made very noticeable at the front of this section. · Setup or Instrumental settings(if applicable) – For more advanced experiments, the experimental setup should be incorporated which includes drawings or images of any equipment that must be constructed or prepared for this lab. · Images not produced by the student should have a reference it the text of the report as well as at the end of the report. · Materials List – the materials that were used in the laboratory should be presented here, in list form. Make sure to include the concentrations of the chemicals as well as their physical states. · Procedure – the procedure includes detailed steps required to perform the experiment. Steps should be written in complete sentences and listed in a numbed format. Things to exclude are gathering of material, trivial manipulations, basic safety practices and general laboratory etiquette. · Ex. “Safety glasses were worn.” “Data was recorded” “Lab area was cleaned.” · Data and Results – This segment of the report should include any data and observations which were collected during the experiment, in the form of tables, graphs, or figures appropriate for the data collected. · Calculations(if applicable) must be shown here. Typically the calculation you perform should be written out in mathematical terms using words or variables rather than actual data. Make sure.

1. Administrator 123
Name
Sample 123 By Administrator Date Wednesday, August 31 2016
Description
4000 600350030002500200015001000
129
57
60
65
70
75
80
85
90
95
100
105
110
115
120
125
cm-1
%T
3058.6
2968.2
2873.9
2826.7
2724.5
1702.5
Guidelines for Written Reports for Chemistry Labs at LU
All lab reports will be submitted to Turn-It-In through
Blackboard.

2. Format: The report must be a typed electronic document, with
reasonable margins and should be double spaced with 12pt.
font. The report should be written in 3rd person past tense.
(“A 20 mL portion of water was dispensed into a beaker.” not “I
took the beaker and dispensed 20 mL of water.”)
The report should include the following components:
· Title Section – This section should include the title of the
experiment, the name of the student author, full names of
experimental partners, and the class and section.
· Introduction – This section should include a very brief
overview of the chemistry/theory involved in the lab.
· History or Background – the report should contain some
simple history or background about the experiment representing
a context for why the experiment matters to the experimenter.
(1-2 paragraphs)
· Theory – The theory should describe the question that you are
trying to answer with this experiment, or the underlying
principle of the experiment. There may be more reactions or
formulae that are the basis for the theory. (1-4 paragraphs)
· Experimental Method – This should be the most detailed
section of the lab report.
· Hazards or Warnings (if applicable) – experimental dangers
should be noted here and should be made very noticeable at the
front of this section.
· Setup or Instrumental settings(if applicable) – For more
advanced experiments, the experimental setup should be
incorporated which includes drawings or images of any
equipment that must be constructed or prepared for this lab.
· Images not produced by the student should have a reference it
the text of the report as well as at the end of the report.
· Materials List – the materials that were used in the laboratory
should be presented here, in list form. Make sure to include the
concentrations of the chemicals as well as their physical states.
· Procedure – the procedure includes detailed steps required to
perform the experiment. Steps should be written in complete
sentences and listed in a numbed format. Things to exclude are

3. gathering of material, trivial manipulations, basic safety
practices and general laboratory etiquette.
· Ex. “Safety glasses were worn.” “Data was recorded” “Lab
area was cleaned.”
· Data and Results – This segment of the report should include
any data and observations which were collected during the
experiment, in the form of tables, graphs, or figures appropriate
for the data collected.
· Calculations(if applicable) must be shown here. Typically the
calculation you perform should be written out in mathematical
terms using words or variables rather than actual data. Make
sure to define the variables and symbols. Then you should show
at least one calculation showing real data with appropriate units
and significant figures.
· Ex: Density (D) = mass/volume and D = 1.25 g/0.97 mL not D
= 1.25 g/0.97 mL
· Discussion – This is the most important part of the lab report!
This section of the report should contain a comparison of the
data collected from known information (if available, either from
references or from instructor provided information) and an
analysis/interpretation of the data obtained.
· Discussion/Conclusions – The conclusion should be answering
the theory question. Discuss how your data does or does not
support the theory presented in the introduction.
· Error analysis – this section may also contain a discussion of
systematic and experimental error. Do not include gross or
human error or any error that was corrected in the process of
completing the experiment. If the results were not similar to
those from correct references, the student may have some reason
or explanation of the erroneous results. The error discussion
should focus not just on identifying the error, but also in
describing how to prevent error.
· References – All reference material that was used to create the
lab reports, including the lab handout/text and any other
references (including websites) should be included here.
· Formatting for references should be consistent throughout the

4. document.
Why lab reports?
The evaluation of experimental work for the field of chemistry
is primarily based on the contents of a written report. Indeed,
the advancement of most scientific endeavors depends on the
exchange of information, usually in written form. No
experimental work is considered completed until the results are
properly reported. These reports should be readable and well
organized.
The goal of a well-written report is to allow someone who
follows the experimenter to duplicate the experiment. The
presentation should be such that the reader is able to follow the
details and obtain a clear idea of what was done and what result
was obtained.
An attempt should be made to use correct spelling and scientific
grammar as though being written as an essay, even though the
report is for use by a scientist rather than for a composition
course.
The report should be concise, while containing as many facts as
necessary to make the report clear. Most importantly, the report
should be an original document containing no paraphrasing, or
copying of materials from textbooks or lab directions or lab
partners.
The instructor will determine the length of the report, but the
report should be complete, and rational. A portion of the
grading of these lab reports will be based on format, focus, and
style. The report should not jump from detail to detail, but
rather flow from beginning to end.
The purpose of this document is to ensure consistency of all
laboratory reports written here at Lindenwood. Most of the
formatting and requirements are similar to how a report would
be required to be written in a non-academic setting.

5. ISOLATION OF A NATURAL PRODUCT BY STEAM
DISTILLATION
Background
The concentration and isolation of an essential oil from a
natural product has had a dramatic impact
on the development of medicine and food chemistry. The ability
to characterize the structure of
the active ingredient from a natural product has permitted
synthesis of this material from other
chemicals, resulting in a reliable and often cheaper sources of
the essential oil. The process often
used in this isolation is called steam distillation. Steam
distillation is an important technique that
has significant commercial applications. Many compounds, both
solids and liquids, are separated
from otherwise complex mixtures by taking advantage of their
volatility in steam. A compound
must satisfy three conditions to be successfully separated by
steam distillation. It must be stable
and relatively insoluble in boiling water, and it must have a
vapor pressure in boiling water that is
of the order of 1 kPa (0.01) atmosphere. If two or more
compounds satisfy these three conditions,

6. they will generally not separate from each other but will be
separated from everything else. The
following example, expressed as a problem, illustrates the
application of steam distillation:
Suppose we have 1 g of an organic compound present in 100 g
of plant material composed mainly
of macromolecular material such cellulose and related
substances. Let's assume that the volatile
organic material has a molecular weight of 150 Daltons, a vapor
pressure of 1 kPa and is not
soluble in water to an appreciable extent. Examples of such
materials characterized by these
properties include eugenol from cloves, cinnamaldehyde from
cinnamon bark or cuminaldehyde
from cumin seeds. How much water must we collect to be
assured we have isolated all of the
natural oil from the bulk of the remaining material?
We can simplify this problem by pointing out that the organic
material is not appreciably soluble
in water. We know from previous discussions that boiling will
occur when the total pressure of
our system equals atmospheric pressure. We can also simplify
the problem by assuming that the
essential oil in not appreciably soluble in the macromolecular

7. material. While in reality this does
not have to be correct, this assumption simplifies our
calculation.
PT = Pwater
obs
+ P
org
obs
o
o
Boiling of our mixture will occur close to 100°C. Remember
that very little oil is soluble in water
which makes the mole fraction of water near unity. Similarly for
the volatile oil, its mole fraction
is also close to one according to our assumption. The total
pressure, PT, is the sum of the vapor
pressure of water, 100 kPa, and the essential oil, P

8. org
o
, 1 kPa. Boiling will occur very close to the
boiling point of pure water. Treating the water vapor and the
organic vapor which are miscible as
ideal, the PV ratio for both vapors is given by the following:
PwaterV/ PorgV = nwaterRT/norgRT;
Pwater/ Porg = nwater/norg and
nwater = wtwater/18; norg = 1/150; rearranging:
wtwater = (100/1)(18/150) = 120 g water or 120 mL
Our calculation suggests that we can be assured that most of the
1 g of the organic matter has been
transferred by the steam if we condense and collect 120 mL of
water. The basis of the separation
by steam distillation is that while the water and organic
condensed phases are immiscible, the
vapors of both are miscible. Once condensed, the two separate
again allowing for an easy
separation. As noted above, both liquids and solids can be
distilled by steam.
In this experiment you will isolate a natural product by steam
distillation and characterize it by its

9. infrared spectrum. The spice you will be given will contain one
of these products shown below.
You will be asked to identify which of the compounds you
isolated by examining the infrared
spectrum of the oil you isolate.
CO2CH3
OH CH3CH
CHO
CH3
CHCH3
CH3
HO
CH3 CH3
CH3
CH2
HO
OCH3
CH2
CH3CH2
O
CH3

10. Procedure
Weigh approximately 5.0 g of spice into a 250 mL round bottom
flask and add 150 mL of water.
Assemble a simple distillation apparatus.
Careful heating is important or frothing may be a problem.
Distill about 50 mL of liquid into a 150 mL Erlenmeyer flask
(or beaker). The distillate may be
cloudy.
Add the distillate to a separatory funnel followed by 10 mL of
dichloromethane.
Gently shake to achieve good agitation and separate the lower
layer (CH2Cl2 layer).
Repeat the extraction again using a second 10 mL portion of
dichloromethane.
Combine the dichloromethane extracts, add enough anhydrous
magnesium or sodium sulfate to
the dichloromethane and swirl until the liquid is no longer
cloudy and there is no aqueous layer on
top.
Decant the product into a tarred 50 mL beaker and evaporate all
the dichloromethane by warming

11. the beaker on a hot plate.
Ask your instructor on how to dispose of the remaining spice
mixture.
Identify the structure of your natural product on the basis of its
infrared spectrum.