FUNCTIONAL GROUP PUBLIC REACTION

A. IMPLEMENTATION PRACTICUM
1. Purpose :To give students experience of the reactions of
functional groups and are able to apply the test this functional group to identify a sample of organic compound.
2. Day & date :Wednesday, June 13, 2012.
3. Place :Laboratory Of Chemistry, FKIP,
University of Mataram.
B. BASIC OF THEORY
The function group is standing in the chemical reactivity of molecules of the group of compounds with specific functional groups showed symptoms of the same reaction. Appropriate reaction to the similarity of symptoms, it can be grouped on the grouping of compounds (Fessenden, 1986: 118).
Aldehyde is a compound wherein a carboxyl functional group bound by an alkyl group. Aldehyde is a compound composed of the elements carbon, hydrogen and oxygen that can be obtained from the oxidation of primary alcohols, chlorides, glycol acid / alkene, hidroformilass (Hart, 2003: 103).
Benedict test is a chemical test to detect reducing sugars in the solution designed by the American chemist, the SR Benedict. This reaction consists of a solution of copper sulfate (CuSO₄), sodium carbonate (Na₂SO₃), and sodium citrate. If the solution is heated together benedict alddehid will happen oxidation to carboxylic acids. Benedict will have reduced to Cu₂O to settle to the bottom of the tube (Sumardjo, 1997: 143).
His reaction:
+ Cu²⁺ + H₂O + Na⁺ H-COONa + Cu₂O + 2H⁺
C. EQUIPMENT AND MATERIALS
1. Tools :
a. Test tube
b. Measuring glass
c. Pipette drops
d. Hot plate
e. Beaker glass
2. Ingredients :
a. Solution of 0.01 M KMnO₄
b. Solution of Cyclohexane
c. Solution of cyclohexene
d. Saturated solution of NaHCO₃
e. Benzoic acid
f. Fehling solution A
g. Fehling solution B
h. Solution of acetaldehyde
i. Solution of 1 M NaOH
j. Solution of Acetone
k. Solution of Iodine
l. Solution of 2 M HCl
m. Solution of aniline
n. Solution of DCM (dicloro methane)
o. Solution of Diethyl ether solution
D. HOW TO WORK
1. Association of Two Carbon-Carbon Multiple
· Reaction with Permanganate
a. Included 1 ml of 0.01 M KMnO₄ in a test tube.
b. Add 2 drops of cyclohexane and shaken.
c. Observed what happened and recorded the results.
d. Repeated the experiment of replacing ac with cyclohexane to cyclohexene.
2. Carbonyl group
· Carboxylic Acid
a. Included 1 ml of a saturated solution of sodium bicarbonate (NaHCO₃) into a test tube.
b. The solution was heated using a hotplate for 10 minutes.
c. 2-3 crystal grains included benzoic acid.
d. Looks closely at what happened.
· Aldehydes
Reaction with Fehling solution:
a. Included 0.5 ml of Fehling solution A (CuSO₄) and 0.5 ml of Fehling solution B (alkaline tartrate solution) into a test tube.
b. Add 1 drop of acetaldehyde and the solution was heated using a hotplate for 1-2 minutes.
c. Observed and recorded the results.
· Ketones
a. Included 1 ml of 1 M NaOH solution into a test tube.
b. Added 1 drop asetophenon or acetone into the solution.
c. Added iodine solution dropwise in Iodid Potassium (KI) to iodine color disappeared.
d. Allowed to stand for several minutes and then removed the color of iodine with a few drops of NaOH solution added.
e. Observed and recorded what happened.
3. Amino group
a. Included 1 ml 2 M HCl solution into a test tube.
b. Add 2 drops of aniline into the tube.
c. Observed and recorded what happened.
4. Compounds Containing Oxygen
a. 1 grain of iodine incorporated into a test tube.
b. DCM was added 0.5 ml (Dichloro Methane).
c. To the solution was added 1 drop of solution of diethyl ether.
E. RESULTS OF OBSERVATIONS
(Attached)
F. DATA ANALYSIS
a. Reaction with Permanganate

b. Carboxylic Acid

c. Aldehyde (Reaction with Fehling solution)

d. Kheton


e. Amino group

G. Discussion
At this time the lab aims to give students experience of the reactions of functional groups and functional groups able to apply this test to identify a sample of organic compounds.
The first experiment is to recognize the double bond carbon-carbon by reaction with permanganate using a sample of cyclohexane and cyclohexene. From the results obtained from samples that showed reactivity that is on the alkene (cyclohexene). This is because the cyclohexene containing double bonds so that when compared with cyclohexane, alkene compounds will be easy to react because of the double bond. Positive results are indicated by color changes are more concentrated, which is dark brown. From the above reaction is very obvious differences. Thus, compounds that would be easy to react is a compound that has a double bond or may be referred to as unsaturated hidrokerbon. While the single-bonded compounds called saturated hydrocarbons.
To recognize the carboxylic acid can be carried out by reacting a solution of saturated NaHCO₃. From the observations that have been made, if the carboxylic acid is reacted with sodium bicarbonate (NaHCO₃) will result in gas bubbles and white milk, and there are white endapat where by using samples of benzoic acid. Hydrogen atom (H) at the carboxyl group (C₆H₅COOH) in benzoic acid can be released as an ion H + (proton), thus providing the acidic nature. Sodium bicarbonate as an additional function of making cakes. NaHCO₃ if treated with any solution will produce gas bubbles.
Aldehyde having at least one hydrogen atom attached to the carbonyl carbon. Aldehydes can be recognized easily because senywa is easily oxidized. One way is to recognize aldehyde Fehling test. Fehling reagent comprises two Fehling A solution that is composed of CuSO₄ and Fehling B solution consisting of sodium potassium nitrate and sodium hydroxide. When Fehling A and Fehling B mixed with an equal volume of the resulting dark blue solution. In the experiment the solution was added 1 drop of acetaldehyde but no change of color in the solution. After heating the color changes to dark green and red colored precipitate occurred. Heating is carried out as Fehling reagent solution is less stable in the cold (low temperature) so that the heating is required in order to Fehling stable. The color change occurs because the compound is oxidized to aldehydes and carboxylic acids formed precipitated Cu₂O red brick.
At this time to recognize the practice carried out by reacting the ketone acetone, iodine and NaOH. This reaction is the oxidation reduction reaction involves an increase and decrease in oxidation. Reactions that occur after mixed with iodine solution changed color from greenish brown menajdi nodes, and then silenced the solution to green color are pale green precipitate. After a few drops of NaOH was added until there is clear and colorless solution gels. Function of the addition of NaOH is as an alkaline environment in the iodoform reaction.
The next is to identify the amino group by reacting with aniline HCl so that when mixed with aniline would clot in HCl solution, indicating that aniline is soluble in HCl. This is because aniline've got more than 5 C atoms which makes the solubility decreases. And when added to HCl, aniline can be dissolved, this is due to NH that is alkaline will tend to react with the acid (HCl).
H. CONCLUSIONS AND RECOMMENDATIONS
1. Conclusion
Based on the objectives, observation and discussion it can be concluded :
· Cyclohexane is a saturated hydrocarbon which is not easy to react, while cyclohexene is an unsaturated hydrocarbon which readily react with KMnO₄.
· Sodium bicarbonate if direaksilkan with benzoic acid will produce a milky white color and there are gas bubbles.
· Compounds with Fehling reactive aldehydes.
· Aniline dissolved in HCl 5%.
· To recognize conducted by reacting the ketone acetone, iodine and NaOH. This reaction is an oxidation reduction reaction.
2. Suggestions:-
BIBLIOGRAPHY

Fessenden, Ralph J. 1986. Organic Chemistry (2nd Edition). USA : Willard Grant Press Publisher.
Hart, Harold. 2003. Organic Chemistry - a short course. Jakarta : Grants.
Sumardjo, Damin. 2005. Basic Chemistry Lab Instructions. Semarang : Undip Press