module_basic and organic chem (eng) 2015.pdf
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LABORATORY GUIDE BOOK BASIC&ORGANIC CHEMISTRY
BASIC CHEMICAL PROCESS LABORATORY
DEPARTMENT OF CHEMICAL ENGINEERING
FACULTY OF ENGINEERING
UNIVERSITY OF INDONESIA
DEPOK 2015
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Basic&Organic Chemistry Laboratory Chemical Engineering Department, Faculty of Engineering Universitas Indonesia
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VISION AND MISSION DEPARTMENT OF CHEMICAL ENGINEERING
VISION
To become a world class Chemical Engineering Department as center of
excellence for education and research in chemical engineering
MISSION
The Department seeks to provide the best quality of undergraduate and
postgraduate education. The Department will provide a broad-based education
and design experience, enabling students to address chemical engineering
problems. Furthermore, the Department will provide students with fundamental
elements to develop in the profession in response to rapidly chaning technology
and societal needs and expectations, and, will also develop important soft skills
such as problem solving, communication, and group skills.
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BASIC & ORGANIC CHEMISTRY LABORATORY
EXPERIMENTS:
1. Physical and Chemical Properties
2. Separation and Purification of Substances
3. Reactions of Acids and Bases
4. The Reaction of Metals with Acids
5. Water Crystals
6. Identification of Hydrocarbon
7. Identification of Alcohol
8. Lipid, Oil, Soap, and Detergent
9. Extraction and Identification of Fatty Acids from Corn Oil
10. Properties of Carboxylic Acids and Esters
11. Carbohydrates
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Laboratory Regulation
1. All practitioners must wear white lab jacket during the lab work.
2. All practitioners must be present 10 minutes before the pre-test begins and sign the
presence list.
3. All practitioners must handle Introduction Report and Lab Journal to the assistant
before the lab begins. All journals can be requested again to the assistant after joining
the pre-test.
4. All practitioners must participate the pre-test before the experiment is done until the
responsible assistant have appraised that he is proper and able to do the given
experiment module. If the practitioners do not join the pre-test, the experiment is
stated as null and void. The pre-test is taken place for 10 to 20 minutes.
5. All practitioners must make a note of all observation results from the experiment that
should be done in the Lab Journal. In the end of the experiment, all the observation
results must be known and signed by the assistant.
6. The lab work report must be completed in a week after the lab work to the assistant.
Delayed report will be given punishment and they will not to be allowed to join the
lab work at transfer of the lab work report.
7. The lab work report that has not fulfilled the requirements must be fixed and handled
to the assistant in a week after it has been stated as a need to be fixed.
8. Borrowing the devices of the lab work must be permitted by the laboratorys
employee and returned them in the same condition.
9. Before leaving the laboratory, practitioners must clean the desk and the equipment;
also put in order the material and the equipment.
10. The use of the equipment and chemical material must be careful, do not spill it.
11. Damage of the castaway equipment/material that happens because of working error
and practitioners negligence must be substituted by the practitioner with the same
equipment/material.
12. Be well mannered to the laboratorys employee and the assistant.
13. The absence of practitioners on the scheduled date will get punishment, and will be
considered as null and void, except there is an acceptable reason e.g. unavoidable
calamity.
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14. The absence caused by sickness, the experiment can be done with the assistants
agreement beyond the lab works schedule, after having the permission from the Lab
works University coordinator. The dispensation of rescheduling that is caused by
sickness only permitted once during the lab works period.
15. The requirements to pass the lab subject:
Have participated in a pre-test and handled the Introduction Report and Journal
before the lab works begun.
Have performed all experiments in the same semester and stated as Pass by the
assistant.
Handle the lab works report for all of the experiments that have been done and
scored by the assistant.
Pass the final test of the lab work.
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Laboratory Report Format
I. PRE-REPORT AND JOURNALWRITING
DATE
EXPERIMENT 1
TITLE
I. OBJECTIVE II. LAB WORK PRINCIPLE III. EQUIPMENT AND CHEMICALS IV. PROCEDURE AND OBSERVATION
EXPERIMENT LAB WORK PROCEDURE OBSERVATION RESULT
A
1.
2.
3.
4.
B
1.
2.
3.
4.
Laboratories :
Name/NPM : 1. . 2. .
Signature of Laboratory Assistant
( )
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II. LAB REPORTWRITING
II.1. COVER
ORGANIC CHEMISTRY LAB REPORT
EVEN/ODD SEMESTER 201/201
GROUP
NAME : 1.
2.
NPM : 1.
2.
BASIC CHEMICAL PROCESS LABORATORY
DEPARTMENT OF CHEMICAL ENGINEERING
FACULTY OF ENGINEERING
UNIVERSITAS INDONESIA
DEPOK 201
II.2. CONTENT
DATE
EXPERIMENT 1
TITLE
I. THEORY
II. DATA PROCESSING
III. OBSERVATION RESULT ANALYSIS
IV. ASSIGNMENT AND QUESTION ANSWER
V. REFERENCE
GROUP :
1. .NPM .
2. .NPM . Signature of Laboratory Assistant
( )
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Common Procedures and Concept
To get an accurate result during the experiment, it is important to know the basic
principle related with laboratory equipment utilization.
I. Heating
Most of heating process in laboratory are done with gas burner. For some cases, we
will use oven equipment during this process. Bunsen burner (from the figure below) usually
has 2 valves for gas and air arrangement.
To turn on a bunsen burner, please follow these steps:
Air valve is in a closed condition,while the gas valve is in an opened condition
Turn it on with matches. From this step, we will see a not-too-hot red flame
To get a better flame and higher temperature from the bunsen burner, open the air valve
slowly until the blue flame appear.
After combustion, turn off the bunsen burner by closing the gas flow.
If the bunsen burner is used for heating a substance in a beaker glass / test-tube , the
steps can be seen from this figure below:
Attention! Dont aim the mouth tube to another peoples face!
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II. Filtration
Filtration aims to separate a liquid substrate from the solids one by passing the
substrate through a filter paper. The filtration procedure is as follows:
Fold the filter paper like the figure below:
Set it on the funnel, then wet the filter paper with distilled water and avoid any air cavity
behind the filter paper.
Note that the position of the filter paper must 0.5-1 cm from the top edge of
the funnel and the amount of sediment is 2/3 from the maximum height of the
filter paper.
Heating or burning process for
components inside the reaction tube.
Heating process of Baker glass using
Bunsen burner.
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Set the funnel in the buffer reservoir dan put the vessel under it.
Pour the liquid substrate through a stirring rod carefully.
Rinse several times with distilled water until completely clean
III. Scale Reading
In a fluid-volume measuring equipment, contained circular lines mark which
indicating the height of limit on the volume of fluid given. As the boundary surface reading is
part of curved liquid, except for liquid whose color is dark, read at the top of the curved
surface of the liquid. More details can be seen in the figure below:
IV. Washing Equipment
All of the equipements used in chemical laboratory must in a clean condition. The
clean equipment can be known when if the surface wetted, there will be a new layer of
distributed liquid. The prescense of fat or dust will cause uneven coating distribution.
Washing/cleaning equipment is done by washing it with detergen , scrubbed it with a
brush if necessary, then rinse it with distillate water. To wash the equipment which is very dirty,
it is important to use potassium dichromate solution in sulfuric acid. How to make the solution
can be asked to the assistant.
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Experiment 1 PHYSICAL AND CHEMICAL
PROPERTIES
I. OBJECTIVES
Distinguishing physical and chemical properties of a substance.
II. INTRODUCTION
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III. EQUIPMENT & CHEMICALS
III.1. Equipment
1. Bunsen
2. Test tube clamp
3. Rubber suction
4. Measuring cylinder 10 ml
5. Ni-Cr wire
6. Test tube
7. Graduated/Measuring pipette
8. Funnel
9. Beaker glass 100 ml
10. Washing bottle & Pipette
III.2. Chemicals
1. Zinc (Zn)
2. Copper (Cu)
3. Magnesium (Mg)
4. Iron (Fe)
5. Aluminum(Al)
6. Calcium carbonate (CaCO3)
7. Cupric nitrate (Cu(N03)2)
8. Calcium hydroxide (KOH)
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9. Concentrated sulfuric acid (concentrated H2SO4)
10. Sodium hydroxide solution (NaOH solution)
11. Acetic acid (CH3COOH)
12. Calcium hydroxide (Ca(OH)2)
13. Hydrochloric acid (HCl)
14. Salt/sugar
15. Methanol/benzene/toluene/ether
16. Wood
17. Calcium carbonate/CaCO3
18. Distillated watert
IV. PROCEDURES
IV.1. Physical Properties
1. Observe and record the shape, color, and smell of the following substances: Methanol,
CaCO3, sugar, Toluene, Benzene, HCl and NaOH.
2. Dissolve each substance in the water. Shake the solution, observe and record the
changes.
3. Do the step number 2 to ether.
4. Explain how to identify substances that have the same shape and color, based on
the physical properties of these substances.
IV.2. Chemical Properties
A. Changes caused by base effect
1. Insert a piece of Al, Zn, Fe and CaCO3 into different test tubes.
2. Add 5 ml of dilute NaOH to each tube. Note the change.
B. Changes caused by acid effect
1. Insert a piece of Cu, Zn, CaCO3 and KOH into different test tubes. Add 3 ml of dilute
HCl to each tubes. Note the change and write the equation of reaction.
2. Pour concentrated H2SO4 into a test tube then insert a piece of wood into it. Note the
change.
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C. Changes caused by heat effect
By using the test tube clamp, heat a piece of magnesium in a bunsen flame. Repeat
this experiment with Cu loops. Note the event that happen.
V. POTENTIAL HAZARDS
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VI. REPORT FORMAT
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Experiment 2 SEPARATION AND PURIFICATION OF
SUBSTANCES
I. OBJECTIVES
To know the types of separation based on the physical and chemical properties.
II. INTRODUCTION
Mixtures are not unique to chemistry; we use and consume them on a daily basis. The
beverages we drink each morning, the fuel we use in our automobiles, and the ground we
walk on are mixtures. Very few materials we encounter are pure. Any material made up of
two or more substances that are not chemically combined is a mixture.
The isolation of pure components of a mixture requires the separation of one
component from another. Chemists have developed techniques for doing this. These methods
take advantage of the differences in physical properties of the components. The techniques to
be demonstrated in this laboratory are the following:
1. Sublimation. This involves heating a solid until it passes directly from the solid phase
into the gaseous phase. The reverse process, when the vapor goes back to the solid phase
without a liquid state in between, is called condensation or deposition. Some solids
which sublime are iodine, caffeine, and paradichlorobenzene (mothballs).
2. Extraction. This uses a solvent to selectively dissolve one component of the solid
mixture. With this technique, a soluble solid can be separated from an insoluble solid.
3. Decantation. This separates a liquid from an insoluble solid sediment by carefully
pouring the liquid from the solid without disturbing the solid (Figure 2.1).
4. Filtration. This separates a solid from a liquid through the use of a porous material as a
filter. Paper, charcoal, or sand can serve as a filter. These materials allow the liquid to
pass through but not the solid (see Figure 2.2 in the Procedure section).
5. Evaporation. This is the process of heating a mixture in order to drive off, in the form of
vapor, a volatile liquid, so as to make the remaining component dry.
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Figure 2.1. Decantation
Figure 2.2. Separation scheme
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III. EQUIPMENT & CHEMICALS
III.1.Equipment
1. Test tube
2. Filter paper
3. Vaporizer bowl
4. Mixer
5. Drop straw
6. Measurement glass 10 ml or 25 ml
7. Wash bottle
8. Bunsen
9. Funnel
10. Watch glass
11. Beaker glass
12. Scale
13. Ni-Cr wire
14. Clamp
III.2. Chemicals
1. KNO3
2. Na2SO4
3. Sodium Cobalt Nitrite
4. Al(OH)3
5. KOH 2 M
6. KCNS
7. Cu(NO3)2
8. NH4Cl
9. BaCl2
10. Fe2O3
11. Dilute HCl
12. Distillated water
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IV. PROCEDURES
IV.1. Separation of substance based on physical properties
IV.1.1. Dissolution and Filtration
The purification or separation mixtures of solid substances and solid substances based
on the solubility difference in substance of a particular solvent.
1. Make a mixture substance with salt and lime with the weight ratio isdetermined by the
assistant (%wt)
2. Weigh the mass of filter paper
3. Dissolute that mixture substance into warm water (200 cc), then write down the
temperature of water, and stir it until the substances dissolve completely.
4. Filter the substance that not soluble, then drying it and weigh it
5. Calculate the mass percent of the salt that can separated before.Give a comment from
your results of observation!
IV.2.2.Crystallization
The separation substance based on the solubility and temperature difference from two
or more of substances.
1. Add 10 ml of distillated water into test tube, then adding KNO3 2 M 3 ml into that test
tube with little CuNO3 (1 spatula). Heating that mixture until soluble, then cooling it
and filtering the crystal that form. Rinsing it with distillated wateruntil the color
disappears.
2. Dissolve a little crystal into the distillated waterand testing ion K with ion specific test.
To another crystal, we do flame test.
IV.1.3. Sublimation
The separation of substances that have a high pressure on temperature basis below the
melting point.
1. Put a mixture of Na2SO4 and NH4Cl (2 grams each) into vaporizer bowl. Heating it
slowly until white steam appears. Put watch glass on bowl, and continuing the heating
until there are no white steam.
2. Collect the white substances that cling on watch glass, then add 10 ml of water. White
substances is divided into 2 parts :
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a. The part where NaCo(NO2)6 is added (sodium cobalt nitrite). Observed and write
down that occurs!
b. The part where BaCl2 is added (Barium Chloride). Observed and write down that
occurs!
IV.2. Separation of substance based on chemical properties
Separation based on amphoteric substance
1. Weigh Al(OH)3 and Fe2O3 (1 grams each)
2. Put the mixture substance into beaker glass 250 ml, adding 15 ml of water and 25 ml
of KOH 2 M, then heat up the solution and stir the solvent until Al(OH)3 soluble.
3. Cool the solution and filtering it. Dissolve the sediment into HCl dilute and test it with
KCNS. Observe what that happen!
4. Add dilute HCl with drop by drop wise into the filtrate. Observe what that happen!
V. POTENTIAL HAZARDS
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VI. QUESTIONS AND PROBLEMS
1. Explain and write down the reaction of sublimation!
2. Determine the percipates that occurs in the above experiment!
VII. REPORT FORMAT
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Experiment3 REACTIONS OF ACIDS AND BASES
I. OBJECTIVES
1. To identicifate acids and bases by investigate the pH of some solutions
2. To know the influence of concentration to the solutions pH
3. To calculate the concentration and the stochiometry of acids and bases
II.INTRODUCTION
We frequently encounter acids and bases in our daily life. Fruits, such as oranges,
apples, etc., contain acids. Household ammonia, a cleaning agent, and Liquid Plumber are
bases. Acids are compounds that can donate a proton (hydrogen ion). Bases are compounds
that can accept a proton. This classification system was proposed simultaneously by Johannes
Brnsted and Thomas Lowry in 1923, and it is known as the Brnsted-Lowry theory. Thus
any proton donor is an acid, and a proton acceptor is a base.
When HCl reacts with water
HCl + H2O H3O+ + Cl
HCl is an acid and H2O is a base because HCl donated a proton thereby becoming Cl, and
water accepted a proton thereby becoming H3O+. In the reverse reaction (from right to left) the
H3O+is an acid and Clis a base. As the arrow indicates, the equilibrium in this reaction lies far to the
right. That is, out of every 1000 HCl molecules dissolved in water, 990 are converted to Cland only
10 remain in the form of HCl at equilibrium. But H3O+ (hydronium ion) is also an acid and can
donate a proton to the base, Cl. Why do hydronium ions not give up protons to Clwith equal ease
and form more HCl? This is because different acids and bases have different strengths. HCl is a
stronger acid than hydronium ion, and water is a stronger base than Cl.
In the Brnsted-Lowry theory, every acidbase reaction creates its conjugate acidbase pair.
In the above reaction HCl is an acid which, after giving up a proton,becomes a conjugate base, Cl.
Similarly, water is a base which, after accepting a proton,becomes a conjugate acid, the hydronium
ion.
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Some acids can give up only one proton. These are monoprotic acids. Examples are
HCl, HNO3, HCOOH , and CH3COOH. The hydrogens circled are the ones donated. Other
acids yield two or three protons. These are called diprotic or triprotic acids. Examples are
H2SO4, H2CO3, and H3PO4. However, in the Brnsted-Lowry theory, each acid is considered
monoprotic, and a diprotic acid (such as carbonic acid) donates its protons in two distinct
steps:
1. H2CO3 + H2O H3O+ + HCO3
2. HCO3 + H2O H3O
+ + CO32
Thus the compound HCO3
is a conjugate base in the first reaction and an acid in the
second reaction. A compound that can act either as an acid or a base is called amphiprotic. In
the self-ionization reaction
H2O + H2O H3O+ + OH
one water acts as an acid (proton donor) and the other as a base (proton acceptor). In
pure water, the equilibrium lies far to the left, that is, only very few hydronium and hydroxyl
ions are formed. In fact, only 1 x 107 moles of hydronium ion and 1 x 107 moles of
hydroxide ion are found in one liter of water. The dissociation constant for the selfionization
of water is
This can be rewritten as
Kw, the ion product of water, is still a constant because very few water molecules
reacted to yield hydronium and hydroxide ions; hence the concentration of water essentially
remained constant. At room temperature, the Kw has the value of
Kw = 1 x 1014 = [1 x 107] [1 x 107
This value of the ion product of water applies not only to pure water but to any
aqueous (water) solution. This is very convenient because if we know the concentration of
the hydronium ion, we automatically know the concentration of the hydroxide ion and vice
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versa. For example, if in a 0.01 M HCl solution HCl dissociates completely, the hydronium
ion concentration is [H3O+] = 1 x 102M.This means that the [OH] is
[OH] =Kw
[H3O+]=
1 x 1014
1 x 102= 1 x 1012M
To measure the strength of an aqueous acidic or basic solution, P. L. Sorensenintroduced the
pH scale.
pH = log[H3O+]
In pure water, we have seen that the hydronium ion concentration is 1 x 107M. The
logarithm of this is -7 and, thus, the pH of pure water is 7. Since water is an amphiprotic
compound, pH 7 means a neutral solution. On the other hand, in a 0.01 M HCl solution
(dissociating completely), we have [H3O+] = 1 x 102M. Thus its pH is 2. The pH scale
shows that acidic solutions have a pH less than 7 and basic solutions have a pH greater than 7.
The pH of a solution can be measured conveniently by special instruments called pH
meters. All that must be done is to insert the electrodes of the pH meter into the
solution to be measured and read the pH from a scale. pH of a solution can also be obtained,
although less precisely, by using a pH indicator paper. The paper is impregnated with organic
compounds that change their color at different pH values. The color shown by the paper is
then compared with a color chart provided by the manufacturer.
There are certain solutions that resist a change in the pH even when we add to them
acids or bases. Such systems are called buffers. A mixture of a weak acid and its conjugate
base usually forms a good buffer system. An example is carbonic acid, which is the most
important buffer in our blood and maintains it close to pH 7.4. Buffers resist large changes in
pH because of the Le Chatelier principle governing equilibrium conditions. In the carbonic
acidbicarbonate (weak acidconjugate base) buffer system,
H2CO3 + H2O H3O+ + HCO3
any addition of an acid,H3O+, will shift the equilibrium to the left. Thus this reduces
the hydronium ion concentration, returning it to the initial value so that it stays constant;
hence the change in pH is small. If a base, OH, is added to such a buffer system, it will react
with the H3O+ of the buffer. But the equilibrium then shifts to the right, replacing the reacted
hydronium ions, hence again, the change in pH is small.
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Buffers stabilize a solution at a certain pH. This depends on the nature of the buffer
and its concentration. For example, the carbonic acidbicarbonate system has a pH of 6.37
when the two ingredients are at equimolar concentration. A change in the concentration of the
carbonic acid relative to its conjugate base can shift the pH of the buffer. The Henderson-
Hasselbalch equation below gives the relationship between pH and concentration.
pH = pKa + log[A]
[HA]
In this equation the pKa is the log Ka , where Ka is the dissociation constant of
carbonic acid
[HA] is the concentration of the acid and [A] is the concentration of the conjugate
base. The pKa of the carbonic acidbicarbonate system is 6.37. When equimolar conditions
exist, then [HA] = [A]. In this case, the second term in the Henderson-Hasselbalch equation
is zero. This is so because [A]
[HA]= 1, and the log 1=0. Thus at equimolar concentration of the
acidconjugate base, the pH of the buffer equals the pKa; in the carbonic acidbicarbonate
system this is 6.37. If, however, we have ten times more bicarbonate than carbonic acid,
[A]
[HA]= 10, then log 10=1 and the pH of the buffer will be
III. EQUIPMENT & CHEMICALS
III.1. Equipment
1. 6 test tubes and its shelf
2. Burette, stand with utility clamp
3. Pipette, volumetric pipette, and graduated pipette
4. Volumetric flask 100 ml
5. Erlenmeyer 250 ml, beaker glass, glass stirring
6. pH paper/pH universal
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III.2. Chemicals
1. Some acids and bases, weak and strong
2. Acids: HCl, HNO3, CH3COOH
3. Bases: NaOH, BaOH2, Mg(OH)2 (or other bases)
4. Indicator phenolphthalein
5. Crystal NaOH
IV. PROCEDURES
IV.1.The Properties of Acids and Bases
1. Ask you assistant to give you 6 acids and bases. Observe and note the color of the
solutions.
3. Take 5 ml of the solution into the test tube. Sign each solution with name L1 until L6.
4. Take the pH paper, dip the edge into the solution. Be careful mot to hit your fingers.
Dry the paper and note the color. Determine the pH of the solution by matching the
color of the pH paper with the instructions in the pH papers box.
5. Do the step A3 for all of the solutions given by the assistant. Note all of the solutions
pH and give sign what solutions are acids and bases. Give basic description of what
you use to distinguish acids and bases.
6. Take one of the acids and bases solution above. Fill into the test tube of each solution 5
ml. Give the sign a0 (acid) and b0 (bases). Perform a ratio of 1:1; 1:10; 1:100; and
1:1000 dilutions. Give the name of each solution a1 until a4 for acids and b1 until b4 for
bases.
7. Measure the pH of each solution as step A2. Record the pH and fill the record into
table accordance with the order of the concentration of the solution.
8. Create a graph of the concentration and pH of the solution. What conclusion that you
get from the experiment?
IV.2. Acids and Bases Reaction
1. Make a solution of 0.1 molar NaOH, HCland acetic acid as 100 ml each. Write the
calculation and how to make the solutions.
2. By using volumetric pipette, take 5 ml of 0,1 molar solution of HCl and put into
Erlenmeyer. Then give 1-2 drops of phenolphthalein indicator. Observe and record the
color.
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3. Fill NaOH solution into the burette and record the volume. Read the scale of the
burette correctly.
4. Perform titration of HCl solution by adding a little NaOH and whipped it at each
addition. Stop the addition ofNaOH right at the time of the change of the solutions
color. Record the volume of NaOH remaining in the burette.
5. Write the acid-base reaction. Calculate the number of moles ofHClaccording to
titrations data and compare the results with theoretical calculation (from the initial
concentration and volume of HCl).
6. Repeat the step 2 to 5 for acetic acid solution.
V. POTENTIAL HAZARDS
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VI. QUESTIONS AND PROBLEMS
1. What is the indicator of the acid-base titration? Explain how to select an indicator for
titration.
2. What is the difference of acids/bases strong and weak? Mention the ways to identify
whether an acid and base is strong or weak.
VII. REPORT FORMAT
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Experiment4 THE REACTION OF METALS WITH
ACIDS
I. OBJECTIVES
1. Qualitative and quantitative analysis related with reactivity reaction between metals
and acid.
2. The used of data titration for stoichiometric reaction calculation.
II. INTRODUCTION
II.1. Reactions of acids with metals
Acids react with most metals and a salt is produced. But unlike the reaction between
acids and bases we don't get any water. Instead we get hydrogen gas.
This is the general word equation for the reaction:
metal + acid salt + hydrogen
II.2. Salts
The salt produced depends upon the metal and the acid. Here are two examples:
zinc + sulphuric acid zinc sulphate + hydrogen
magnesium + hydrochloric acid magnesium chloride + hydrogen
It doesn't matter which metal or acid is used, if there is a reaction we always get
hydrogen gas as well as the salt.
II.3.The test for hydrogen
There is a simple laboratory test to see if a gas is hydrogen. A lighted wooden splint
goes pop if it is put into a test tube of hydrogen. This is because the flame ignites the
hydrogen, which burns explosively to make a loud sound.
II.4. Acids and hydrogen
All acids contain hydrogen atoms. Apart from hydrochloric acid, this is not clear from
their names, but you can tell they contain hydrogen from their chemical formulae. Remember
that the chemical symbol for hydrogen is H.
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III. EQUIPMENT & CHEMICALS
III.1.Equipment
1. Glass funnel and filter paper
2. Five test tubes
3. Five erlenmeyer flask 100ml and watch glass
4. Burette, clamp, and balance
5. Pipette, Volumetric pipette, and measuring cylinder
6. Volumentric flask 50 ml
III.2. Chemicals
1. Metal powder Zn (zinc), Cu (copper), Fe (iron) and Al (aluminum)
2. 6 M HCI andNaOH solution
3. Methyl orangeindicator
IV. PROCEDURES
IV.1. Qualitative Observation
1. Provide 4 pieces of test tubes, and fill each tube with 6M HCl solution 5ml. Label it
S1 s/d S4.
2. Weigh each 0,1 gr metals Zn, Fe, Cu and Al. Then, insert those metals to the
test tubes Sl s/d S4. Observe and note the changes happened.
3. If the metals reactivity can be seen from the amount of gas formed, order the metals
reactivity based on your observation!
4. Write down the reaction equation from this experiment and suggest an experiment to test
what kind of gas formed on the reaction above.
IV.2. Quantitative Observation
1. Provide 5 pieces of clean erlenmeyer flask 100 ml. Label itSl s/d S5.
2. Fill each erlenmeyer with 6M HCl 10 ml (use volumetric pipette 10ml, measure it
correctly), then close it with watch glass. Calculate the mole of HCl, and write down
the aswer.
3. Insert Zn, Fe, Cu and Al metals 0,2 gr each into erlenmeyer S1 s/d S4 . Solution in
erlenmeyer S5 will be reacted with nothing.
4. Note when the metals reacted, and let the reaction happened for 30-40 minutes.
(determined by the assistant).
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5. After the reaction finish, separate the metals from the solution with the filtration process (wet
the filter paper with distillated watert before use it in filtration process).
6. Take the solution from erlenmeyer Sl s/d S5 2 ml each, and add 1-2 drops of methyl
orangeindicator. Observe and write down the color.
7. Titrate the solution with 1.0 M NaOH solution. Calculate the total amount of mole
HCl after reaction.
8. Calculate the HCl conversion with the formula below:
(Amount of mole HCl reacted)
(Amount of mole HCl before the reaction) 100%
9. Make a table/graph between the type of metals vs %-HCl conversion. Order the
metals based on their reactivity, and compare this result with the result from
experiment A.
V. POTENTIAL HAZARDS
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VI. QUESTIONS AND PROBLEMS
1. Is there any effect from the location of these metals in periodic table and their
reactivity to react with acid? Explain!
2. What factor affect the rate of reaction in general as long as you know?
VI. REPORT FORMAT
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Experiment5 WATER CRYSTALS
I. OBJECTIVES
1. To learn dehidration activity and hidration of a solid containing water crystals.
2. To calculate the empiric formula of water crystals.
II. INTRODUCTION
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III. EQUIPMENT & CHEMICALS
III.1. Equipment
1. Threepyrextest tubes
2. Droplet pipette and wood clamp
3. Three vaporazer cup
4. Bunsen burner
III.2. Chemicals
1. Solid materials containing water crystals:CuSO4.XH2O,
MgSO4.XH2O,CaCl2.XH2O.
2. Distillated water
IV. PROCEDURES
IV.1. Qualitative Observation
1. Ask a assistant 3 kinds of solid materials containing crystalline water. Observe and
write down the name of the substance and their colors.
2. Insert those substance into a pyrex test tube each. Label it .
3. Use a wood clamp to hold the test tube, then heat the substance in the tube on the
bunsen burner. Observe and write down the changes happened.
4. Then, drop a water into the test tube. Obseve and write down the changes
happened.
5. Write down the reaction equation, all of the heating and watter addition activity.
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Explain those equation and the difference between those substance based on your
observation.
IV.2. Quantitavie Observation
1. Provide3 piecesof ceramicbowls(evaporator. Weighand write down
theweightcarefully.
2. Insert solids substance containing crystalline water into the third cup, and write down
the weight. Determine the weight of the substance
3. Heat the cup containing sample until they change color just as color samples of
uniform / homogeneous (color sample has changed all of the colors before
warming),stop heating and immidiately weigh carefully weighed.
4. Calculate the weight loss after heating. If weight loss is showing the amount of water
contained in the crystal sample, determine the empiric formula of crystal water, then
compare with the theoritical and empiric formula.
5. Try this experiment for three different sample and show the similiarities and
differences of your observations
V. POTENTIAL HAZARDS
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VI. QUESTIONS AND PROBLEMS
1. Write down the name, empiric formula, color, and physical properties from 3 kind
of solid substance containing crystal water.
2. Give an example in chemical engineering industries which use dehydration and
hydration process.
VI. REPORT FORMAT
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Experiment 6 IDENTIFICATION OF HYDROCARBON
I. OBJECTIVES
To identify several properties of hydrocarbon.
II. INTRODUCTION
Numerous numbers of organic compounds is made by the carbon atoms which attract
one another and other molecule that are able to make bond with known carbon group. To
make it simple, we can say that hydrocarbon is a compound with bond between hydrogen and
carbon only.
Hydrocarbon has many bonds, but can be grouped by their unique characters where
these structures are also suit with the general chemical reactivity. Then every group can be
grouped from its structure or reactivity. In this test, practitioner will test the chemical
reactivity from saturated, unsaturated, and aromatic hydrocarbon.
II.1. Hydrocarbon Structure
Hydrocarbon can be considered saturated if there is maximum number of hydrogen
which is bonded to carbon. It is happen if the carbons bonded as single bond or it is called as
sigma bond (). Ethane is an example for saturated hydrocarbon with these criteria.
Unsaturated hydrocarbon has less number of hydrogen which can make bond from its
maximum number. This compound must have double bond so that the total number of
covalent bond is four. Ethylene and acetylene are examples for this compound.
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Double carbon bonds from ethylene consist of one bond which is the same with
saturated hydrocarbon and one pi bond (). Both of them can form double bond, while
acetylene has triple bond with one bond and two bonds.
Aromatic hydrocarbon has unique bond within its carbon which is difficult to explain.
In benzene, one of aromatic hydrocarbon, all of the carbon bonds are identical (six bonds).
Two type of benzene bonds, a and b, have single and double bonds which are varied.
But, both of them represent a different molecule. Structure (c), using circle inside the
hexagon, can be accepted. The circle represents the six electrons which are distributed evenly
at the aromatic bond at six carbon atoms. The bonds which are represented by the
hexagonal side are bond. Structure (c) can be used to represent all kind of carbon bonds
inside the benzene correctly.
II.2. Reactivity of Hydrocarbon
The bond from saturated bond (alkane) is very stable so it is not reactive. At high
temperature, saturated hydrocarbon can react with oxygen (combustion). From this reaction,
carbon bonds are broken and the products are carbon dioxide and water. If the combustion is
not efficient, then carbon monoxide or even single carbon (soot) can be produced. But,
generally, saturated hydrocarbon is combusted more efficiently than other types of
hydrocarbon.
The hydrogen-carbon bond from alkane can be replaced by halogen. General reaction
for bromine is:
Look at the equation, HBr is a product from the reaction. To react with halogen, we
need heat or light energy.
The bond from unsaturated hydrocarbon (alkene and alkyne) is reactive and it is
easier for additional reaction to happen. In this reaction, a molecule like bromine forms two
single bonds of carbon-bromine which is in one bond energy level. Ethylene reacts with
bromine to form 1,2-dibromothane.
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This reaction happens in room temperature. As the product, a character of brownish
red from bromine is disappeared. We should also pay attention to the reaction that there is no
HBr produced like in the substitution reaction for saturated hydrocarbon. Acetylene has two
bonds which occur additional reaction:
The bond from aromatic compound is hold out in the reaction. Even for saturated
group which make bond with benzene ring can be attacked by oxidizing agents with a very
large energy. The product which is produced when single group alkyl bonded with benzene
ring is benzoic acid.
Hydrogen atom from benzene can be substituted by bromine, but it needs catalyst Fe.
Look that the following reaction is a substitution reaction and HBr is produced.
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III. EQUIPMENT & CHEMICALS
III.1. Equipment
1. Testtube 10 x 75 mm
2. Testtube 16 x 150 mm
3. Generator acetylene
4. Pipette
5. Watch glass
6. Test tube rack
III.2. Chemicals
1. Heptane
2. Octene
3. Toluene
4. Xylene
5. Butanol
6. Carbon tetrachloride
7. 1% vol bromine in carbon tetrachloride
8. Iron tack
9. 1% wt potassium permanganate solution
10. Unknown sample
11. Calcium carbide
12. Litmus paper
IV. PROCEDURES
Caution: all organic waste must be thrown at the right place.
Note:
5. Do all the following experiments below.
6. Experiment A until D use three types of hydrocarbon: heptane, 1-octene, and toluene.
Use clean and dry test tubes for all reactions. The structure for the three compounds
are :
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7. Most alkanes contain alkene as pollutant. To clean the pollutant, alkane is mixed with
H2SO4 with the ratio alkane: H2SO4 = 3:1. It will form a layer, where the lower layer
which is darker (H2SO4) is separated. The remaining alkane layer is treated again with
H2SO4 until it do not form anymore darker layer. Then, alkane is washed by water. (be
careful with H2SO4 solution, can be performed only by expert).
IV.1. Solubility of Hydrocarbon
1. Shake slowly the 0.5 mL heptane with 5 mL water solvent in test tube 16x150 mm to
test its solubility. Write down your observation.
2. Repeat step 1 with other samples: 1-Octene and toluene, each with same ratio.
3. Change the solvent with 1-butanol and ligroin (mix of alkane), repeat step 1 and step 2
with same ratio.
IV.2. Flammability of Hydrocarbon
Attention: Hydrocarbon is highly flammable, and its vapor is very explosive in air. Be
careful with the flame. Do not add the quantity of the hydrocarbon as it has already been set
in this experiment.
1. Expel three drops of one type of hydrocarbon sample on the watch glass, by using
matches/lighter, light the hydrocarbon.
2. Observe the type and color of the flame, carbon in the flame and the remaining
residue.
3. Repeat the above steps for other two hydrocarbons.
4. Write down your observation.
IV.3. Effect of Bromine in Carbon Tetrachloride
1. Put 1 mL bromine in carbon tetrachloride in a small test tube.
2. Add 10-20 drops of hydrocarbon sample, observe the change of colour.
3. If there is no colour change after 20 drops, add iron tack, and wait for 5 minutes.
4. If there is still no colour change, heat the solution in a hot water bath for 15-20
minutes.
5. To test if there is hydrogen bromide, place blue litmus paper at the tip of the test tube.
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6. Repeat the experiment with two other sample of hydrocarbon.
7. Write down your observation.
IV.4. Reaction with Potassium Permanganate
1. Place 1 mL sample of hydrocarbon in a small test tube.
2. Add 3 drops of 1% potassium permanganate solution.
3. Shake the test tube, observe all the changes that happen. How long does it need for the
changes to start?
4. Repeat with another sample of hydrocarbon.
5. Write down your observation.
IV.5. Grouping The Substance
1. Get unknown samples from your laboratory assistant.
2. Do the tests to group the samples to saturated, unsaturated, and aromatic.
IV.6. Preparation and Chemical Properties of Acetylene
1. Pay attention to the instrumentation of acetylene consists of a dry 250 mL bottle with
two rubber stopper, a dropping line, glass tubing, and appropriate rubber.
2. Put some pieces of calcium carbide (CaC2) inside the dry bottle.
3. Add the water carefully and slowly to a certain degree to form acetylene gas.
4. To dry the test tube 16x150 mm with 10 drops of 1% bromine in carbon tetrachloride
solution, add about 3 mL carbon tetrachloride. Flow the acetylene to the solution.
Observe the changes that happen.
5. For the 16x150 mm test tube which has 3 drops of 1% potassium permanganate, add
about 3 mL water. Flow the acetylene to the solution until the colour of permanganate
is disappeared. If the reaction is slow, shake and continue the flow of acetylene.
Repeat until the colour disappears. Observe the changes that happen.
6. Write down your observation.
V. POTENTIAL HAZARDS
Flame risk from heating chemical. Use gloves when heating the chemicals with
Bunsen or with water bath.
Heptane
- Breathing vapors may cause drowsiness and dizziness. Causes eye, skin, and
respiratory tract irritation. Aspiration hazard if swallowed. Can enter lungs and
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cause damage. Dangerous for the environment.
- Wear protective gloves,clothing and masker to prevent exposure.
1-octene
- Causes eye, skin, and respiratory tract irritation. Toxic to aquatic organisms, may
cause long-term adverse effects in the aquatic environment. Aspiration hazard if
swallowed. Can enter lungs and cause damage. May cause central nervous system
effects.
- Wear protective eyeglass, gloves,clothing to prevent exposure.
Toluene
- Causes eye irritation. Prolonged or repeated contact can defat the skin and lead to
irritation and/or dermatitis. Inhalation causes headaches, dizziness, drowsiness,
nausea, and respiratory irritation. If swallowed, causes headaches, dizziness,
drowsiness and nausea, and may lead to unconsciousness. Harmful or fatal if liquid
is aspirated into lungs. Danger! Contains Benzene. Cancer hazard. Can cause blood
disorders. Harmful when absorbed through the skin.
- Wear chemical goggles, protective gloves, and clothing to prevent exposure.
Xylene
- Hazardous in case of skin contact (irritant, permeator), of eye contact (irritant), of
ingestion, of inhalation.
- Wear splash goggles, lab coat, and gloves.
1-butanol
- Causes severe eye irritation and possible eye injury.Breathing vapors may cause
drowsiness and dizziness. Causes skin and respiratory tract irritation. May be
harmful if swallowed. Aspiration hazard if swallowed. Can enter lungs and cause
damage. May cause central nervous system depression.
- Wear chemical splash goggles, protective gloves, and clothing to prevent exposure.
Carbon tetrachloride
- May be fatal if inhaled, absorbed through the skin or swallowed. Causes eye, skin,
and respiratory tract irritation. Aspiration hazard if swallowed. Can enter lungs and
cause damage. Cancer suspect agent. May cause liver and kidney damage. May
cause central nervous system effects. This is a CFC substance which destroys
ozone in the upper atmosphere. Destruction of the ozone layer can lead to increased
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ultraviolet radiation which, with excess exposure to sunlight, can lead to an
increase in skin cancer and eye cataracts. Marine pollutant.
- Wear chemical safety goggles, protective gloves, and clothing to prevent exposure.
Bromine
- Strong oxidizer. Contact with other material may cause a fire. Corrosive. Causes
eye and skin burns. May cause severe respiratory tract irritation with possible burns.
May cause severe digestive tract irritation with possible burns. Lachrymator
(substance which increases the flow of tears). May cause central nervous system
effects. May cause cardiac disturbances. May cause liver and kidney damage.
- Wear chemical goggles and face shield, protective gloves, and clothing to prevent
exposure.
Calcium carbide
- Dust may irritate respiration system, serious burns may occur because chemical
reacts quickly with water to form acetylene & calcium hydroxide in vigorously
exothermic reaction. Acetylene may displacing oxygen.
- Wear chemical safety goggles, protective gloves, and clothing to prevent skin
exposure.
VI. QUESTIONS AND PROBLEMS
Give the products these following reactions:
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VII. REPORT FORMAT
Name ______________ Date ______________
Partner ______________ Lab. Assistant ______________
REPORT SHEET
Solubility of Hydrocarbon
Sample Solubility
Water 1-butanol Ligroin
heptane
1-octene
toluene
Flammability of Hydrocarbon
Sample Flammability
Type Color Carbon Total Residue
heptane
1-octene
toluene
Effect of Bromine in Carbon Tetrachloride
Sample Change of Color
10-20 drops Iron Tack Heating Blue Litmus Paper
heptane
1-octene
toluene
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Name ______________ Date ______________
Partner ______________ Lab. Assistant ______________
REPORT SHEET
Reaction with Potassium Permanganate
Sample Reaction
3 drops After shake Time
heptane
1-octene
toluene
Grouping The Substance
Sample Grouping
Saturated Unsaturated Aromatic
1
2
3
Preparation and Chemical Properties of Acetylene
Sample Change
carbon tetrachloride Water Shake
carbon tetrachloride - -
potassium permanganate -
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Experiment 7 IDENTIFICATION OF ALCOHOL
I. OBJECTIVES
To identify several properties of alcohol.
II. INTRODUCTION
Alcohol can be said as organic solvent which is analog to water. In alcohol, hydroxyl
group (-OH) is attached to saturated carbon not at the hydrogen atom as in water. The
hydroxyl group makes physical and chemical properties very different with hydrocarbon.
Structure from hydroxyl group which is strongly affected character of alcohol is a polar bond
between hydrogen-oxygen and a pair of electrons from the oxygen.
Some chemical differences from alcohol depends on the alkyl group structure. One
important thing is how many carbon atom which is bonded with the C-OH group. Primer,
secondary, and tertiary alcohol have 1,2, and 3 carbon group consecutively, which is attached
at the carbon atom bonded to oxygen atom.
Hydroxyl group from alcohol can make hydrogen bond with water. That is why,
alcohol is soluble in water than in hydrocarbon. All alcohol with low molecular weight is
completely soluble in water, and the solubility of high molecular weight is more likely to
alkanes solubility. As the size of alkyl group increase, the polar hydroxyl group will give
less contribution to physical properties.
Proton from water molecule is more acidic than proton from hydroxyl group. That is
why proton from hydroxyl group can only be neutralized by strong alkaline.
Proton from hydroxyl group from water can be reduces by active metal and produces
hydrogen gas. This reaction is between active metal and water.
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Rate of this reaction depends on the alcohol acidity. The most acidic component will
be the most reactive agent to sodium.
Hydroxyl group from alcohol can be replaced by other groups such as halogen. The
rate of reaction depends on the structure of alkyl group. The replacement of hydroxyl group
from chlorine group can be done with some reagent. One of the example is Lucas reagent
which consists of ZnCl2 and HCl.
For tertiary alcohol, the reaction is very fast in room temperature. Secondary alcohol
reacts in 5-10 minutes. Primary alcohol can react after hours in room temperature. Because
alkyl chloride is not soluble in Lucas reagent, then the turbidity means that the reaction has
occurred. Time needed to start the reaction indicates the type of structure in alcohol.
Primary, secondary, and tertiary alcohols give different reaction to oxidizing agents.
Type of oxidizing agent which is typically used is sodium dichromate (Na2Cr2O7) in dilute
sulphate acid solution.
Chromium is reduced to Cr3+ in the reaction. Dichromate solution is yellowish orange,
while Cr3+ is green. Therefore, the alcohol oxidation by potassium dichromate is indicated by
the change of colour from chromium species.
The structure of alcohol below reacts continuously with iodine and NaOH to produce
iodoform, yellow solid.
This reaction can be used to characterize the structure of alcohol.
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III. EQUIPMENT & CHEMICALS
III.1. Equipment
1. Test tube 10x75 mm
2. Test tube 16x150 mm
3. Beaker glass
4. Pipettes
5. Test tube rack
III.2. Chemicals
1. Methanol
2. Ethanol
3. 1-propanol
4. 2-propanol
5. 1-butanol
6. 2-butanol
7. 2-methyl-2-propanol
8. 1-pentanol
9. 1-octanol
10. 1% Sodium dicromate solution (Na2Cr2O7 . 2H2O)
11. 1M NaOH solution
12. 6M HCl solution
13. Iodine-Potassium iodide solution
14. Lucas reagent
IV. PROCEDURES
IV.1. The Solubility of Alcohol in Water
1. Put 1 ml of water in small test tube.
2. Add some drops of ethanol while shaking until it does not soluble anymore or until
the volume is twice from initial volume of water.
3. Repeat the test with another alcohol (1-butanol, 2-butanol, 2-methyl-2-propanol, 1-
pentanol, and 1octanol).
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4. Characterize each alcohol: soluble, a litte soluble, or totally soluble. Write down on
your report.
IV.2. Reactivity of Alcohol with Sodium
1. Your laboratory assistant will react sodium metal with methanol, ethanol, 1-propanol,
2-propanol, and 2-methyl-2-propanol.
2. Write down your observation in report, write down the chemical equation from these
reactions.
3. Put the level of acidity of alcohol in order from their O-H bonds.
IV.3. Lucas Test
1. Put 1 ml of 1-butanol in 16 x 150 mm test tube, add Lucas reagent.
2. Close the test tube, mix the solution until it is soluble by shaking. Settle down in room
temperature.
3. Observe what happens after 5 minutes and after 30 minutes.
4. Repeat the test with other samples: 2-butanol and 2-methyl-2-propanol.
5. Write down your observation and write down the chemical equation from these
reactions.
6. If there is no reaction, mark with NR.
IV.4. Oxidizing Alcohol
1. Put 1 ml of alcohol samples and add 10 drops of HCl 6 M in test tubes.
2. Add 1 drop of 10% Na2Cr2O7 solution and mix them well.
3. Look and observe the change of colour.
IV.5. Iodoform Reaction
1. Add 4 drops of 1-propanol in 1 mL of methanol and 1 mL of water.
2. Add 2 ml of NaOH 3M solution.
3. Add drop by drop the I2-KI solution until yellow solid forms, CHI3 , or until the
colour is brown after the mixing at least 2 minutes.
4. Settle down the test tube for 5 minutes, observe what happens.
5. Repeat the test by changing 1propanol with 2-propanol, 2-butanol, and 2-methyl-2-
propanol.
6. Write down your observation.
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V. POTENTIAL HAZARDS
Methanol
- Toxic by ingestion and inhalation. Can be toxic by skin absorption.Affects central
nervous system, especially optic nerve.Causes dizziness, nausea, muscle weakness,
narcosis, respiratory failure.Prolonged or repeated skin contact may cause
irritation.
- Wear safety glasses, protective clothing and masker to prevent exposure
Ethanol
- Flammable liquid and vapor. Cause severe eye irritation and moderate skin
irritation.
- Wear protective clothing and masker to prevent exposure.
1-propanol
- May cause eye and skin irritation. May be harmful if swallowed. May cause
respiratory tract irritation. May cause central nervous system depression. May
cause dermatitis. Hygroscopic (absorbs moisture from the air).
- Wear chemical goggles , protective clothing and masker to prevent exposure
2-propanol
- May cause central nervous system depression. May form explosive
peroxides.Hygroscopic (absorbs moisture from the air). Causes respiratory tract
irritation. Aspiration hazard if swallowed. Can enter lungs and cause damage. This
material has been reported to be susceptible to autoxidation and therefore should
be classified as peroxidizable. Causes eye irritation. Breathing vapors may cause
drowsiness and dizziness. Prolonged or repeated contact causes defatting of the
skin with irritation, dryness, and cracking.
- Wear chemical goggles , protective clothing and masker to prevent exposure
1-butanol
- Causes severe eye irritation and possible eye injury.Breathing vapors may cause
drowsiness and dizziness. Causes skin and respiratory tract irritation. May be
harmful if swallowed. Aspiration hazard if swallowed. Can enter lungs and cause
damage. May cause central nervous system depression.
- Wear chemical splash goggles, protective gloves, and clothing to prevent exposure.
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2-butanol
- Breathing vapors may cause drowsiness and dizziness. Causes eye and respiratory
tract irritation. May form explosive peroxides.
- Wear chemical splash goggles, protective gloves, and clothing to prevent exposure.
1-pentanol
- Hygroscopic (absorbs moisture from the air). May cause eye irritation. May cause
irritation of the digestive tract. May cause central nervous system depression. May
cause burning sensations, coughing, wheezing, laryngitis, shortness of breath and
headache. Harmful if inhaled.
- Wear protective gloves, and clothing to prevent exposure.
1-octanol
- Causes eye and skin irritation.May cause respiratory tract irritation. May cause
central nervous system depression.
- Wear chemical splash goggles, protective gloves, and clothing to prevent exposure.
Sodium dicromate solution (Na2Cr2O7 . 2H2O)
- Potentially fatal if swallowed, harmful on contact with the skin, respiratory tract
burns, skin burns, eye burns, mucous membrane burns, allergic reactions, cancer
hazard (in humans)
- Wear chemical goggles , protective gloves, and clothing to prevent exposure.
NaOH solution
- Mucous membrane irritant. Skin: severe irritation, sensitization, dermatitis &
burns. Eyes: irritation,conjunctivitis& burns. Ingestion: damage to mucous
membranes or tissues.
- Wear protective gloves, and clothing to prevent exposure.
HCl solution
- Corrosive to skin, eyes, nose mucous membranes, respiratory & gastrointestinal
tract. Inhalation:respiratory tract irritation/infection. Severe & fatal
gastrointestinal burns w/necrosis. Severe burns to eyes & blindness. Changes in
pulmonary function, chronic bronchitis,dermatitis, tooth erosion, & conjunctivitis.
- Wear splash chemical goggles, protective gloves, and clothing to prevent
exposure.
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Iodine-Potassium iodide solution
- May cause respiratory tract irritation. May cause skin irritation. May cause eye
irritation. May cause digestive tract irritation.
- Wear chemical safety goggles , protective gloves, and clothing to prevent
exposure.
VI. QUESTIONS AND PROBLEMS
1. 1,2-Hexanediol is very soluble in water, while 1-hexanol is not soluble. Explain the
reasons.
2. A lab researcher has 4 compounds (a, b, c, d) with chemical formula C4H10O. All the
compounds react with sodium and free hydrogen. In Lucas test, compound d reacts
very fast b reacts after heated, while a and c react but very slow. Write down the
structure of b and d! What is the possible structure of a and c?
3. A compound with formula C3H8O does not react with sodium, Lucas reagent, or
sodium dichromate solution. Write down the structure. Explain the character of the
not reactive compound!
4. There are 8 isomeric alcohol with formula C5H12O. Only two of them react with
iodoform test. Write down the structure of the two compounds.
5. Write down the products from the reactions below, if there is no reaction happens,
write NR:
a.
b.
c.
d.
e.
f.
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g.
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VII. REPORT FORMAT
Name ______________ Date ______________
Partner ______________ Lab. Assistant ______________
REPORT SHEET
The Solubility of Alcohol in Water
Sample Characterize
Soluble Little Soluble Totally Soluble
ethanol
1-butanol
2-butanol
2-methyl-2-propanol
1-pentanol
1octanol
Reactivity of Alcohol with Sodium
Sample Reactivity
Change Chemical Equation Level of Acidity OH-Bond
methanol
ethanol
1-propanol
2-propanol
2-methyl-2-propanol
Lucas Test
Sample Lucas Test
5 minute 10 minute Chemical Equation
1-butanol
2- butanol
2-methyl-2-propanol
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Name ______________ Date ______________
Partner ______________ Lab. Assistant ______________
REPORT SHEET
Oxidizing Alcohol
Iodoform Reaction
Sample Color Change
1 drop Shake
methanol
ethanol
1-propanol
2- propanol
1-butanol
2-butanol
2-methyl-2-propanol
1-pentanol
1octanol
Sample Amount I2-KI Color Change
2 minutes 5 minutes
methanol
1-propanol
2- propanol
2-butanol
2-methyl-2-propanol
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Experiment 8 LIPID, OIL, SOAP, AND DETERGENT
I. OBJECTIVES
1. To understand several properties of oil and lipid
2. To understand the soap-making procedures
3. To know the existence of phosphate in commercial detergent
II. INTRODUCTION
Triglyceride, one kind of lipid, is ester from alcohol glycerol and long chain
carboxylic acid.
Triglyceride consists of acid with 8 to 12 carbon atom and mix of different types of
acid. If most of the acid is not saturated, then glycerides will be liquid and classified as oil.
Glycerides which have more saturated acid will have higher melting point and classified as
lipid/fat.
Hydrolysis of lipid or oil with base will produce glycerol and salt from the acid, it is
known as saponification. Soap is salts from long chained carboxylic acid. Sodium and
potassium salts are water soluble, while salts from magnesium, calcium, and iron are not
water soluble.
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Detergent is salts from aryl sulfonates or alkyl sulfates.
Since calcium salts from aryl sulfonate and alkyl sulfate are water soluble, detergent
is usually used in hard water, while soap will produce not soluble precipitate.
Every year, Americans use millions kilogram of detergent to wash clothes or other
things. Nearly every gram from detergent flows to lake or river. Most of laundry products
contain phosphate which will make algae fertile in the water. Phosphate act as fertilizer to
algae in the same form as phosphate when it make plants or grass fertile in garden. Algae
consume dissolved oxygen in water in a large number. Concentration of dissolved oxygen
will reduce so it be difficult for the life of fishes or other sea animal, hence, it will disturb
ecosystem equilibrium.
In this experiment, commercial detergent will be tested to know the existence of
phosphate in it. The basic of this reaction is chemical reaction between phosphate anion and
molybdate anion in acid solution.
Ammonium molybdate solution, (NH4)6Mo7O24, is added to former acidic solution. If
the sample contains phosphate anion, precipitate of ammonium phosphomolybdate
(NH4)3PMo12O40will be well separate and light yellow solid will form.
In this experiment, practitioners will be asked to bring a few sample of liquid or
powder detergent. Make sure to check the label to determine whether the product contain
phosphate. The sample will be tested with other practitioners samples to know whether there
is phosphate or not.
III. EQUIPMENT & CHEMICALS
III.1. Equipment
1. 16 x 150 mm test tube
2. 10 x 75 mm test tube
3. Reflux instrument
4. Pipettes
5. Glass stirring rod
6. Beaker glass
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III.2. Chemicals
1. Cotton seed oil
2. Hexane
3. Carbontetrachloride
4. 5% Bromine in carbontetrachloride solution
5. Ethanol 95%
6. NaOH solution
7. High concentration of HCl solution
8. A piece of soap
9. Calcium chloride 0.1 M
10. Magnesium chloride 0.1 M
11. Iron (III) chloride 0.1 M
12. Ammonium molybdate solution 0.2 M
13. Nitric acid 6M
14. Litmus paper or pH indicator paper
15. Mineral oil
IV. PROCEDURES
IV.1. The Solubility of Cotton Seed Oil
1. Put 0.5 mL (about 10 drops) cotton seed oil in each four 16x150 mm test tubes.
2. Add 1 mL of water to the first tube, 1 mLof ethanol to the second tube, 1 mL of
hexane to the third tube and 1 mL carbon tetrachloride to the fourth tube.
3. Shake the test tubes, write down the solubility of each solution in the test tube.
4. Add 5 mL of additional solvent.
5. Shake each tube strongly, observe if the oil is soluble now.
6. Write down your observation.
IV.2. Unsaturated Triglyceride
1. Use 2 mL of the solution between carbon tetrachloride and cotton seed oil which has
been done in experiment A for this experiment.
2. Add drop by drop 5% Bromine in carbon tetrachloride solution.
3. Calculate the amount of drops needed to produce bromine color effect of the solution.
4. Put 0.1 g of Crisco into 1 mL of carbon tetrachloride.
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5. Repeat step 2 and 3.
6. Write down your observation.
IV.3. Soap
Attention: Sodium hydroxide is caustic compound, do not touch this compound. Wash your
hands as soon as you feel soapy. Sodium hydroxide can cause eye irritation and
blindness. Clean up the contaminated equipment.
IV.3.1. Preparation
1. Fuse 5 g of sodium hydroxide into 10 mL of distillate water and into 25 mL ethanol in
125 mL Erlenmeyer flask, put 5 g of triglyceride into the reflux flask.
2. Add some boiling chips into the flask.
3. Prepare the reflux instrument as it is shown in Picture 14. Ask your assistant to check
your tool.
4. Reflux the flask content for about 30 minutes or until the solution becomes pure and
homogen.
5. Move the soapy solution from heat, cool the flask and add about 80 mL of high
concentrated sodium chloride solution.
6. Shake the solution comprehensively and collect precipitated soap with the absorb
filtration.
IV.3.2. Equipment
1. Prepare 1 g of soap solution (from the previous result of reflux) in 50 mL boiling
distillate water.
2. Prepare the same solution with commercial soap and detergent.
IV.3.3. Alkaline Characteristic
1. Test the pH from each solution with Litmus paper.
2. Write down your observation.
IV.3.4. Emulsion Characteristic
1. Place 3 drops mineral oil to each four test tubes.
2. Put in 5 mL of distillation water to the first tube, 5 mL soap solution (experiment
result) to the second tube, 5 mL commercial soap to the third tube and 5 mL detergent
solution to the fourth tube.
3. Shake each tube for a minute.
4. Write down your observation.
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IV.3.5. The Effect of Metal Salt
1. Put 5 mL of your soap solution experiment to each three test tubes.
2. Add2 mLof Calcium chloride 0.1 M to the first tube, Magnesium chloride 0.1 M to
the second tube and Iron (III) chloride 0.1 M to the third tube.
3. Write down your observation.
4. Repeat this experiment with commercial soap and detergent solution.
IV.4. Phosphate Qualitative Test in Detergent
1. Phosphate test is very sensitive. Therefore, wash your test tube until clean or you
better use other new test tube.
2. Add about 60 mg phosphate (like a grain of hulled rice) to the test tube.
3. Add 8 drops of HNO3 6 M. Detergent that contains carbonate will cause foaming
when HNO3 is added. If this happens, keep up adding drop by drop of HNO3 until the
foam is not formed. Then, add again 8 drops of HNO3.
4. If the detergent is in liquid form then use about 15-20 drops in this experiment.
5. Using the magnetic stirrer, mix the solution smoothly.
6. Add 2 drops of ammonium molybdate solution 0.2 M and heat the tube in hot water
for about 5 minutes.
7. If it contains phosphate, yellow precipitate will appear.
V. POTENTIAL HAZARDS
Cotton seed oil
- May cause irritation. This is expected to be a low hazard for usual industrial
handling.
- Wear appropriate protective eyeglasses, protective gloves, and protective clothing
to prevent skin exposure.
Hexane
- Extremely flammable liquid and vapor. Vapor may cause flash fire. Possible risk
of impaired fertility. Breathing vapors may cause drowsiness and dizziness.
Dangerous for the environment. May cause nervous system effects.
- Wear appropriate protective eyeglasses, protective gloves, and protective clothing
to prevent skin exposure
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Carbontetrachloride
- May be fatal if inhaled, absorbed through the skin or swallowed. Causes eye, skin,
and respiratory tract irritation. Aspiration hazard if swallowed. Can enter lungs
and cause damage. Cancer suspect agent. May cause liver and kidney damage.
May cause central nervous system effects. This is a CFC substance which destroys
ozone in the upper atmosphere. Destruction of the ozone layer can lead to
increased ultraviolet radiation which, with excess exposure to sunlight, can lead to
an increase in skin cancer and eye cataracts. Marine pollutant.
- Wear chemical safety goggles, protective gloves, and clothing to prevent exposure.
Bromine
- Strong oxidizer. Contact with other material may cause a fire. Corrosive. Causes
eye and skin burns. May cause severe respiratory tract irritation with possible
burns. May cause severe digestive tract irritation with possible burns.
Lachrymator (substance which increases the flow of tears). May cause central
nervous system effects. May cause cardiac disturbances. May cause liver and
kidney damage.
- Wear chemical goggles and face shield, protective gloves, and clothing to prevent
exposure.
NaOH
- Mucous membrane irritant. Skin: severe irritation, sensitization, dermatitis &
burns. Eyes: irritation,conjunctivitis& burns. Ingestion: damage to mucous
membranes or tissues.
- Wear protective gloves, and clothing to prevent exposure.
HCl solution
- Corrosive to skin, eyes, nose mucous membranes, respiratory & gastrointestinal
tract. Inhalation:respiratory tract irritation/infection. Severe & fatal
gastrointestinal burns w/necrosis. Severe burns to eyes & blindness. Changes in
pulmonary function, chronic bronchitis,dermatitis, tooth erosion, & conjunctivitis.
- Wear splash chemical goggles, protective gloves, and clothing to prevent
exposure.
Soap
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- May cause eye and skin irritation. May cause respiratory and digestive tract
irritation. Good laboratory procedures are recommended when handling this
compound. This is expected to be a low hazard for usual industrial handling.
- Wear appropriate protective clothing to prevent skin exposure.
Calcium chloride
- May cause severe eye, skin and respiratory tract irritation with possible burns.
May be harmful if swallowed. May cause cardiac disturbances. Hygroscopic
(absorbs moisture from the air).
- Wear splash chemical goggles, protective gloves, and clothing to to minimize
contact with skin.
Magnesium chloride
- May cause eye irritation.
- Wear splash chemical goggles, protective gloves, and clothing to to minimize
contact with skin.
Iron (III) chloride
- Harmful if swallowed, inhaled or absorbed through skin.
- Wear splash chemical goggles, protective gloves, and clothing to prevent exposure.
Ammonium molybdate
- Causes eye and skin burns. Strong oxidizer. Contact with other material may
cause a fire. Causes severe digestive and respiratory tract burns.
- Wear protective goggles, protective gloves, and clothing to prevent exposure.
Nitric acid
- May be fatal if inhaled. Causes severe eye and skin burns. Causes severe
respiratory and digestive tract burns. Strong oxidizer. Contact with other material
may cause a fire. Acute pulmonary edema or chronic obstructive lung disease may
occur from inhalation of the vapors of nitric acid. Corrosive to metal.
- Wear chemical splash goggles and face shield, butyl rubber gloves, and clothing
to prevent skin exposure
Mineral oil
- May cause eye and skin irritation. May cause respiratory and digestive tract
irritation.
- Wear appropriate protective eyeglasses, protective gloves, protective clothing to
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prevent skin exposure.
VI. QUESTIONS AND PROBLEMS
1. From all of the solvents that have been experimented, which is the best solvent to
vanish oil stain or fat from clothes?
2. How many gram of bromine needed to react completely with 1 mol triglyceride that
contains only oleic acid?
3. Why do we use saturated concentration sodium chloride solution to precipitate soap?
4. What reaction will happen when calcium ion is added to the soap solution?
5. Do metal salt solution from the carboxylic acid and sulphate alkyl look the same as the
metal salt solution from CO32- and SO4
2-
6. Arsenate Ion, AsO43- will react with ammonium molybdate, same with phosphate.
Explain why and what ion will be produced?
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VII. REPORT FORMAT
Name ______________ Date ______________
Partner ______________ Lab. Assistant ______________
REPORT SHEET
The Solubility of Cotton Seed Oil
No. Sample Solubility
Shake Add Solvent Shake
1 Water
2 Ethanol
3 Hexane
4 Carbon tetrachloride
Unsaturated Triglyceride
No Sample Amount of Drops Need
1 Cottonseed Oil
2 Crisco
Soap
Alkaline Characteristic
No Sample Colour of Litmus Paper
1 Soap
2 Commercial soap
3 Detergent
Emulsion Characteristic
No Sample Characteristic
1 Mineral Oil
2 Soap
3 Commercial Soap
The Effect of Metal Salt
No. Sample Solution
Calcium chloride Magnesium chloride Iron (III) chloride
1 Soap
2 Commercial soap
3 Detergent
Experiment 9
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EXTRACTION AND IDENTIFICATION OF FATTY ACIDS FROM CORN OIL
I. OBJECTIVES
To extract fatty acids from neutral fats.
To convert them to their methyl esters.
To identify them by thin-layer chromatography.
II. INTRODUCTION
Fats are esters of glycerol and fatty acids. Liquid fats are often called oils. Whether a
fat is solid or liquid depends on the nature of the fatty acids. Solid animal fats contain mostly
saturated fatty acids, while vegetable oils contain high amounts of unsaturated fatty acids. To
avoid arteriosclerosis, hardening of the arteries, diets which are low in saturated fatty acids as
well as in cholesterol are recommended.
Note that even solid fats contain some unsaturated fatty acids, and oils contain
saturated fatty acids as well. Besides the degree of unsaturation, the length of the fatty acid
chain also influences whether a fat is solid or liquid. Short chain fatty acids, such as found in
coconut oil, convey liquid consistency in spite of the low unsaturated fatty acid content. Two
of the unsaturated fatty acids, linoleic and linolenic acids, are essential fatty acids because the
body cannot synthesize them from precursors; they must be included in the diet.
The four unsaturated fatty acids most frequently found in vegetable oils are:
All the C=C double bonds in the unsaturated fatty acids are cis double bonds, which interrupt
the regular packing of the aliphatic chains, and thereby convey a liquid consistency at room
temperature. This physical property of the unsaturated fatty acid is carried over to the
physical properties of triglycerides (oils).
In order to extract and isolate fatty acids from corn oil, first, the ester linkages must be
broken. This is achieved in the saponification reaction in which a triglyceride is converted to
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glycerol and the potassium salt of its fatty acids:
In order to separate the potassium salts of fatty acids from glycerol, the products of
the saponification mixture must be acidified. Subsequently, the fatty acids can be extracted
by petroleum ether. To identify the fatty acids that were isolated, they must be converted to
their respective methyl ester by a perchloric acid catalyzed reaction:
The methyl esters of fatty acids can be separated by thin-layer chromatography (TLC).
They can be identified by comparison of their rate of migration (Rf values) to the Rf values of
authentic samples of methyl esters of different fatty acids (Fig. 4.1).
Figure 4.1 TLC Chromatogram
Rf = distance travelled by fatty acid/distance travelled by the solvent front.
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III. EQUIPMENT & CHEMICALS
III.1. Equipment
1. Aluminum foil
2. Polyethylene gloves
3. 15 x 6.5 cm silica gel TLC plate
4. Capillary tubes open on both ends
5. Heat lamp
6. 18.Water bath
7. Ruler
8. Drying oven, 110 OC
III.2. Chemicals
1. Corn oil
2. Methyl palmitate
3. Methyl oleate
4. Methyl linoleate
5. Petroleum ether (b. p. 3060 OC)
6. 0.5 M KOH in ethanol
7. Concentrated HCl
8. Anhydrous Na2SO4
9. Methanol: perchloric acid mixture (95:5)
10. Hexane: diethyl ether mixture (4:1)
11. Iodine crystals, I2
IV. PROCEDURES
IV.1. Extraction of Fatty Acids
1. Weigh a 50-mL Erlenmeyer flask and record the weight on your Report Sheet (1).
2. Add 2 mL of corn oil and weigh it again. Record the weight on your Report Sheet (2).
3. Add 5 mL of 0.5 M KOH in ethanol to the Erlenmeyer flask. Stopper it. Place the
flask in a water bath at 55 OC for 20 min.
4. When the saponification is completed, add 2.5 mL of the concentrated HCl. Mix it by
swirling the Erlenmeyer flask. Transfer the contents into a 50-mL separatory funnel.
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Add 5 mL of petroleum ether. Mix it thoroughly. Drain the lower aqueous layer into a
flask and the upper petroleum ether layer into a glass-stoppered test tube. Repeat the
process by adding back the aqueous layer into the separatory funnel and extracting it
with another portion of 5 mL of petroleum ether. Combine the extracts.
IV.2. Preparation of Methyl Esters
1. Place a plug of glass wool (the size of a pea) into the upper stem of a funnel, fitting it
loosely. Add 10 g of anhydrous Na2SO4. Rinse the salt on to the glass wool with 5 mL
of petroleum ether; discard the wash. Pour the combined petroleum ether extracts into
the funnel and collect the filtrate in an evaporating dish. Add another portion (2 mL)
ofpetroleum ether to the funnel and collect this wash, also in the evaporating dish.
2. Evaporate the petroleum ether under the hood by placing the evaporating dish on a
water bath at 60 OC. (Alternatively, if dry N2 gas is available, the evaporation could be
achieved by bubbling nitrogen through the extract. This also must be done under the
hood.)
3. When dry, add 10 mL of the CH3OH:HClO4mixture (95:5). Place the evaporating dish
in the water bath at 55 OC for 10 min.
IV.3. Identification of Fatty Acids
1. Transfer the methyl esters prepared above into a separatory funnel. Extract twice with
5 mL of petroleum ether. Combine the extracts.
2. Prepare another funnel with anhydrous Na2SO4 on top of the gla