example.docx Example Qualitative Analysis Goals Utilize physical, chemical and spectroscopic data to identify structure of unknown compounds. After purifying the unknown solution, determine boiling point, measure RI, perform solubility and potassium permanganate test and obtain spectral data. This will provide sufficient data to identify the structure and identity of the unknown compound. Procedure Density: Unknown example #1 in avail was obtained from the TA. The density of the liquid was measured by obtaining a graduated cylinder. The graduated cylinder was weighted before and after addition of the unknown sample. We calculate the density by using density equation [D=mass/volume] RI: Next, the RI was measured. A few drops of the unknown were added to the refrectometer. We adjusted it so field of view has well defined light and dark split. Then, the “read” button was pushed to record the RI and temperature. Solubility Test: A small vial was obtained and 20 drops of unknown sample were mixed with 25 drops of concentrated sulfuric acid. The contents of the test tube were mixed and the subsequent change in color to rustic red was noted. Potassium Permanganate Test: 1 cm of unknown was mixed with 10 drops of KmNO4 and the change of color & phase separation was noted. Boiling point: The sand was heated and 0.4 mL of the unknown is placed on the top of the sand. The thermometer was placed on the top as well. The temperature was noted once the sample starts boiling. Chemical Reactions Observations Solubility Test: When sulfuric acid was mixed with unknown sample, the reaction color changed from clear to rustic red. The change in color indicated that our sample is soluble in sulfuric acid and thus, cannot be alkyl halide, which is no soluble in sulfuric acid. Potassium Permanganate Test: When 1 cm of unknown was mixed with 10 drops of KmNO4 there was a phase separation as well as color change. The top layer was dark purple and the bottom was pink. Also, there was a slight precipitate. Results Density: The weight of vial = 11.4356 g Vial+ sample = 12.053 g 12.053-11.4356 =0.6174 g Density=mass/volume 0.6174 g/ 1 mL = 0.6537 g/mL RI: Index of refraction read: 1.4942 at 23.65 C IR correction: nobs + 0.00045 (t-20) 1.4942+0.00045(23.65-20)=1.4925 For proper identification of our unknown sample #1, we used the following experimental results: Type of Test Observed values Boiling point 85 C Density 0.6537 g/mL RI (read) 1.4942 at 23.65 C RI (corrected) 1.4925 at 20 C Solubility test: When Sample #1 mixed with sulfuric acid it produced to color change to rustic red. Potassium Permanganate Test: When the sample mixed with KmNO4, there was a phase separation with dark purple color in the top, pink at the bottom and slight precipitate. IR: H NMR Discussion Qualitative analysis is the way to identify unknown compound by obtaining physical and chemical properties for this compound. Some of these physical properties are boiling point, RI, ...

1. example.docx
Example
Qualitative Analysis
Goals
Utilize physical, chemical and spectroscopic data to identify
structure of unknown compounds. After purifying the unknown
solution, determine boiling point, measure RI, perform
solubility and potassium permanganate test and obtain spectral
data. This will provide sufficient data to identify the structure
and identity of the unknown compound.
Procedure
Density:
Unknown example #1 in avail was obtained from the TA. The
density of the liquid was measured by obtaining a graduated
cylinder. The graduated cylinder was weighted before and after
addition of the unknown sample. We calculate the density by
using density equation [D=mass/volume]
RI:
Next, the RI was measured. A few drops of the unknown were
added to the refrectometer. We adjusted it so field of view has
well defined light and dark split. Then, the “read” button was
pushed to record the RI and temperature.
Solubility Test:
A small vial was obtained and 20 drops of unknown sample
were mixed with 25 drops of concentrated sulfuric acid. The
contents of the test tube were mixed and the subsequent change
in color to rustic red was noted.
Potassium Permanganate Test:
1 cm of unknown was mixed with 10 drops of KmNO4 and the
change of color & phase separation was noted.
Boiling point:
The sand was heated and 0.4 mL of the unknown is placed on

2. the top of the sand. The thermometer was placed on the top as
well. The temperature was noted once the sample starts boiling.
Chemical Reactions
Observations
Solubility Test:
When sulfuric acid was mixed with unknown sample, the
reaction color changed from clear to rustic red. The change in
color indicated that our sample is soluble in sulfuric acid and
thus, cannot be alkyl halide, which is no soluble in sulfuric
acid.
Potassium Permanganate Test:
When 1 cm of unknown was mixed with 10 drops of KmNO4
there was a phase separation as well as color change. The top
layer was dark purple and the bottom was pink. Also, there was
a slight precipitate.
Results
Density:
The weight of vial = 11.4356 g
Vial+ sample = 12.053 g
12.053-11.4356 =0.6174 g
Density=mass/volume
0.6174 g/ 1 mL = 0.6537 g/mL
RI:
Index of refraction read: 1.4942 at 23.65 C
IR correction:
nobs + 0.00045 (t-20)
1.4942+0.00045(23.65-20)=1.4925
For proper identification of our unknown sample #1, we used
the following experimental results:
Type of Test
Observed values
Boiling point
85 C

3. Density
0.6537 g/mL
RI (read)
1.4942 at 23.65 C
RI (corrected)
1.4925 at 20 C
Solubility test:
When Sample #1 mixed with sulfuric acid it produced to color
change to rustic red.
Potassium Permanganate Test:
When the sample mixed with KmNO4, there was a phase
separation with dark purple color in the top, pink at the bottom
and slight precipitate.
IR:
H NMR
Discussion
Qualitative analysis is the way to identify unknown compound
by obtaining physical and chemical properties for this
compound. Some of these physical properties are boiling point,
RI, and density. Boiling point is the temperature at which the
vapor pressure of a liquid is the same as the atmospheric
pressure. Refractive index is a measure of how much light is
bent of reflected that inters the liquid. Also, density is mass per
volume. We use these physical properties to identify our
unknown sample. For instance, by comparing the observed
boiling point with theoretical boiling point. Also, obtained RI
should be compared with the theoretical RI of the original

4. compound. Furthermore, we can compare observed density with
theoretical one to make sure we have the correct compound.
For chemical test, we can obtain the structure and molecules in
the compound. For NMR, we can figure out the compound
formula. For IR, we can identify the type of bonds and
functional groups presented in the compound.
Based on results we obtained, out compound shows that it is
Ethyl Acetate. We figure this out by comparing the observed
physical properties with the theoretical properties as illustrated
in the table below:
Type of Test
Observed values
Theoretical Values
Boiling point
85 C
76-77 C
Density
0.6537 g/mL
0.902 g/mL
RI (read)
1.4942 at 23.65 C
RI (corrected)
1.4925 at 20 C
1.37
Also, solubility test shows that it is soluble, so this is an
indication that it is alkene, alkyne or diene. By using potassium
permanganate test, (by using 10 drops of KMnO4 and 1 cm-
which equals to 10 drops- of sample), there were a phase
separation which is an indication that is alkene only. Also, by
using H NMR and IR, we can confirm our findings. In H NMR,
since there are 3 types of hydrogens in Ethyl Acetate, one is
singlet, one is quartet, and one is triplet, it confirms that there

5. are 3 types of hydrogens. For IR, bands at 1300 that is C-O for
Esters.
In this experiment, everything was clear since we did much of
those techniques in Organic Lab I.
Conclusion
In this experiment, we use qualitative analysis to identify out
unknown sample by using chemical and physical properties. W
compared physical properties that we obtained with the
theoretical properties for the original compound. Also, we use
potassium permanganate test to identify if the compound or
alkene, alkyne or diene as well as using solubility test. Also, we
use chemical test such as NMR and IR to identify the structural
formula and functional groups that are presented in the
compound.
Post Lab Questions
1. KMnO4 molecular weight : 158.03 g/mol , 100 mL solution
or 0.1 L
0.5 moles/L X 0.1 L= 0.05 moles of KMnO4 X 158.03 g/mol=
7.90 g KMnO4
18 M of H2SO4, we need 1M, 100 mL solution
(1M)(100 mL)/ 18M=5.65 H2SO4
2. Since the unknown was not soluble in sulfuric acid, then, it
must be an alkyl halide. Based on the given physical properties
(BP: 150 C, Density: 1.50 g/mL) the compound must be 1-Ido-
3-methylbutane, which has boiling point of 147 C and density of
1.521 g/mL.
3. The unknown liquid is soluble in sulfuric acid, hence, it is
not alkyl halide. It must be an alkene, alkyne, or diene. Since
the potassium permanganate test was positive and the unknown
require half number of drops of reagent required for the known
alkene, then the unknown must be an alkyne or a diene. Based
on the given physical properties (BP: 116-120 C, density: 0.90
g/mL, the compound must be 1,3-cycloheptadiene, which has a
boiling point of 120-121 C and density of 0.868 g/mL.

6. H313C O
O
+
HO
S
OH
O
O
Ethyl Acetate Sulfuric Acid
H313C O
O
Ethyl Acetate
O
MnO
O
O-
K+

7. Potassium Permanganate
+
H
3
13
C
O
O
+
HO
S
OH
O
O
Ethyl Acetate
Sulfuric Acid
H
3
13
C
O
O
Ethyl Acetate
O
Mn
O
O
O
-
K
+
Potassium Permanganate
+

8. LabReport-
SynthesisOfAlkenesViaAcidCatalyzedDehydrationOf3comma3-
dimethyl-2-butanol.docx
Procedure we follow:
Set up glassware and add reagents
10ml H3PO4 and 10 ml alcohol in 25 ml flask
reflux and distilled collect distillate in glassware that is in ice
perform separation
10 ml separator funnel
but during experiment, we didn’t collect ditilled due to an error
in the apparatus
so we use another group distillation and we didn’t use
separatory funnel
Overall Chemical Equation: Use ChemDraw; Use chemical
structures and not the general formula for the compounds.
Provide the structure of all 3 possible alkenes for the reaction
(1.5 /30 points)
Reaction Mechanism:(I DO MEAN FULL MECHANISM!)
(arrows must be shown, but can be hand drawn); Mechanism
shall include the formation of all 3 possible alkenes for the
reaction. (2.5/30 points)
Procedure: Describe any changes performed in the original
procedure. Describe as well what was in your original
procedure.
(1/30 points)
Observations: No data presentation;
(1/30 points)
Results: Report all of your data acquired here, no data
discussion. Use the measurements recorded during your

9. experiment; they will be compared to the data you left behind
for your TAs. Report your all data in a clear way.
Divide your results in parts:
Calculations: Use the alcohol density to calculate its mass from
the volume you pipette in lab; Use the mass of alcohol to
calculate how much alkene shall be formed. The reaction with
Phosphoric Acid is a 1:1 reaction. Since all the three alkenes
have the same molecular formula, they are constitutional
isomers. The amount (meaning the mass) you expect to obtain is
then the addition of the mass for each of the three possible
alkenes. Use the total mass measured for the alkenes at the end
of the experiment to calculate the percent yield for the
reaction.
GC analysis: Attach your chromatographs; include the controls
for your experiment. Do not forget the table legend.
RI: construct a table (do not forget the legend!) including the
RI for:
· 3,3-dimethyl-2-butanol
· 3,3-dimethyl-1-butene
· 2,3-dimethyl-2-butene
· 2,3-dimethyl-1-butene
· All the fractions collected after the final distillation
Spectroscopic Analysis:
IR Spectroscopy: Identify the main peaks in the functional
group part of your IR spectra for alcohol and final products.
Have one IR spectrum for each of the fractions collected at the
end of the experiment. Look at the C-H bending bands in the
fingerprinting region of your spectra and indicate the “type” of
alkenes it indicates (terminal, cis, trans,….)
Discussion: Discussion is dissertative. Use “It” instead of “I,
She/He” when writing the discussion.
Your discussion shall explain (not necessarily in the sequence
below):
· What is the function of Phosphoric Acid in this reaction?

10. · Phosphoric Acid is not as common in laboratory than
Hydrochloric Acid, for example. Why in this reaction HCl
would be a poor choice of reagent?
· Due to the volatile character of the alkene products, the
distillate must sit on a ice-water bath. What is volatility and
how it affects the results of the reaction?
· Once the alcohol and acid are heated and the reaction distilled,
you will obtain a mixture of water and alkenes (all three
possible alkenes). Your procedure asks for not allowing the
products to sit, instead to proceed with the extraction and
washing of organic phase. Explain why the organic and aqueous
phase must be separated faster.
· The stability of alkenes is usually defined by the number of
hydrogens around the double carbon-carbon bond. Look at the
structure of the three possible alkene products and predict
which of them is the most the most stable (and therefore the one
present in higher concentration)
· Summarize the RI data. Does your data support pure alkene
fractions?
· Discuss your GC data, what can be said in terms of number of
alkene products and identity (when compared to the alcohol and
alkene products).
· Discuss your IR spectra. Do your data support the conversion
of alcohol to alkene? Looking at the C-H bending region of
spectra, what can be said of the type of alkene (cis, trans,
terminal, tri-substituted….) present in your spectra?
· Discuss your 1H-NMR spectra.
· Discuss your missteps during this reaction and your reaction
yield. If your data do not support pure alkene separation, what
you would do to obtain pure alkenes? What would you do
different and/or how could you minimize the product loss?
(9/30 points)
Conclusion: what is your conclusion (what did you learned from
your experiment?). Be sure your conclusion will correlate the
goals you have for your experiment. It is fine to break your

11. conclusion in parts. (2/30 points)
Part-B-
SynthesisOfAlkenesViaAcidCatalyzedDehydrationOf3comma3-
dimethyl-2-butanol.pdf