10-14 functional group analysis

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Experiment # 10-14Analysis of Functional Groups: Hydrocarbons, Alcohols & Phenols, Aldehydes & Ketones,

Carboxylic Acid & Acid Derivatives, and Amines

Christian Cruz

Date Performed: Date Submitted: August 24, 2010

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Hydrocarbons

Flammability of Aliphatic and Aromatic HydrocarbonsProcedure The test samples used and their appearance are as follows:

Methane, ethylene, and acetylene are colorless gases Cyclohexane and toluene are colorless liquids

A test tube containing the sample gas was ignited using a Bunsen burner flame. The mouth of the tube, when stopper was taken out, was moved nearer the Bunsen burner flame. When the flame ignited, the color of the flame and the soot produced were observed.

Reaction InvolvedExpected Results Experimental Results / Observations

When the test samples were ignited with a Bunsen burner flame, the following happened:

Methane gas did not react since there was no flame color and soot produced

Ethylene gas produced an orange flame but no soot Acetylene gas produced a bright yellow flame and there was

soot Cyclohexane produced a yellow flame but there was no soot Toluene produced a yellow flame and soot

Inference

Reaction with Bromine waterProcedure The test samples were methane, ethylene, and acetylene which are

colorless gases.Bromine water is a yellow brown solution.1 mL of bromine water was added to the test tube containing the gas sample then it was stoppered immediately then shaken.

Reaction Involved

Expected Results Bromine water changes from yellow brown to colorless when its bonds break.Methane will not react with bromine water since it does not contain a reactive site. Ethylene and acetylene are unsaturated compounds which mean that they have reactive sites therefore; they can react with bromine so a color change from brown yellow to colorless should be observed.

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Experimental Results / Observations

When 1 mL of bromine water was added to the samples, the following happened:

Methane gas did not react since no color change happened to the bromine water

Ethylene gas produced a yellow then colorless liquid Acetylene gas produced a pale yellow liquid and smoke

evolved Inference Methane is saturated (alkene).

Ethylene and Acetylene are unsaturated (alkene and alkyne).

Reaction with Alcoholic IodineProcedure The test samples were methane, ethylene, and acetylene which are

colorless gases. Other samples were naphthalene and cyclohexane which are colorless liquids. Alcoholic Iodine is a yellow liquid.2 drops of alcoholic iodine was added to the test tube containing the sample then it was shaken until a change occurs.


When 2 drops of alcoholic iodine was added to the test samples, the following happened:

Methane gas produced a yellow solution Ethylene gas produced an orange solution Acetylene gas did not react since there was no color change in

the alcoholic iodine Naphthalene produced a clear yellow solution Cyclohexane produced two immiscible layers: the top layer

was yellow and the bottom layer was clearInference Methane is saturated (alkene).


Baeyer’s Test for UnsaturationProcedure The test samples were methane, ethylene, and acetylene which are

colorless gases. Other samples were naphthalene and toluene which are colorless liquids. Alkaline Potassium Permanganate is a purple liquid.1 mL of 1% alkaline potassium permanganate was added to the test tube containing the sample.

Reaction Involved

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Expected Results When alkaline potassium permanganate reacts, it reduces to manganese dioxide which is a brown solid.Methane will not react with alkaline potassium permanganate since it does not contain a reactive site.Ethylene and acetylene are unsaturated compounds which mean that they have reactive sites so they can react with alkaline potassium permanganate so a color change from purple to brown should be observed. Naphtalene and Toluene are aromatic compounds which means that they can undergo substitution reaction therefore they can react with alkaline potassium permanganate so a change should be observed.

Experimental Results/ Observations

The following happened when 1% alkaline potassium permanganate was added to the samples:

Methane gas did not react with potassium permanganate since there was no color change

Ethylene gas produced a chocolate brown solution Acetylene gas produced a dark brown solution with dark

brown precipitate Naphthalene produced a violet solution with purple precipitate Toluene produced two immiscible layers: the top layer was

clear and the bottom layer was purpleInference Methane is saturated (alkene).


Formation of Copper AcetylideProcedure The test samples were methane, ethylene, and acetylene which are

colorless gases.Ammoniacal cuprous chloride is a dark blue solution. 5 mL of ammoniacal cuprous chloride was added to a test tube containing the sample then; it was covered by a stopper and shaken.

Reaction Involved CuCl

C2H2 CuC2H2 + 2HClExpected Results Experimental Results / Observations

When 5mL ammoniacal cuprous chloride was added to methane and ethylene, there was no reaction since the ammoniacal cuprous chloride remained dark blue.When 5mL ammoniacal cuprous chloride was added to acetylene,

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brown precipitates were produced which are sticking at the sides of the test tube.

Inference

Reaction of Bromine with Aromatic HydrocarbonProcedure The sample used is toluene which is a clear liquid.

Bromine in chloroform is a light yellow liquid.1 mL of toluene was placed into two separate test tubes. Each test tube was added with bromine in chloroform until a faint yellow color was obtained then, one test tube was placed under the sun and the other was moved in a dark place (inside the locker).

Reaction Involved

Expected Results Bromine will react to an aromatic compound by substitution if it is initiated by producing bromine radicals through UV light. When bromine forms radicals, or when their bond is broken, there will be a color change from light yellow to colorless. This means that a color change should happen in the test tube, with bromine in chloroform and toluene, which is placed under the sun.


When toluene and bromine in chloroform was mixed, the solution produced was dark brown.The test tube, which was placed inside the locker (a place without sunlight), containing toluene and bromine in chloroform remained dark brown in color.The test tube, which was placed under the sun, containing toluene and bromine in chloroform became colorless.

Inference Bromine only reacts with aromatic hydrocarbons when initiated with UV light coming from the sun.

Action of Nitric Acid with Aromatic HydrocarbonProcedure The samples used were toluene and cyclohexane which are colorless

liquids. Concentrated sulfuric acid and Nitric acid solutions are colorless liquids.6 drops of sample was added to a test tube containing 2 mL of concentrated sulfuric acid and 1 mL of concentrated nitric acid. The test tube was heated through a water bath for 10 minutes and it was cooled then; the contents were poured in 10 mL ice water.

Reaction InvolvedExpected Results

UV

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When concentrated sulfuric acid and concentrated nictric acid were added to the samples, the following were observed:

In toluene, two colorless immiscible layers formed. In cyclohexane, two immiscible layers formed: the top layer is

yellow and the bottom layer is clear.When the solutions were heated using a water bath and poured to ice water, the following happened:

The toluene solution still remained colorless and white vapor evolved

The cyclohexane solution turned milky white and white vapor evolved

Inference

Alcohols & Phenols

Sodium Detection for Acid HydrogenProcedure Sodium metal is a grayish white solid.

The dry alcohol sample was prepared by adding a pinch of anhydrous magnesium sulfate to 95% ethanol then the solution was decanted. The solution produced was a colorless liquid. Sodium metal was added to the sample and the mixture was heated through water bath then, 1 mL of water was added and the solution was tested using litmus paper.

Reaction Involved

Expected Results When sodium metal reacts with alcohol, hydrogen gas is liberated, indicated by bubble formation. The reaction between dry alcohol and sodium metal should produce bubbles due to the formation of acid hydrogens (then hydrogen gas) and a basic solution die to the formation of a sodium compound.


When sodium metal and water were added to the dry alcohol and after it was cooled, bubbles were produced at the surface of the settled sodium metal.

Inference Acid hydrogen is present in the dry alcohol sample.

Comparison of Oxidizing ConditionsProcedure The sample was ethyl alcohol which is a colorless liquid.

6M sulfuric acid and 6M sodium hydroxide are colorless liquids.1 % potassium permanganate is a purple solution.5 drops of ethyl alcohol and 2 mL of water were mixed in each three test tubes. One test tube was added with a drop of 6M sulfuric acid, the other test tube was added with 6M sodium hydroxide, and the last test tube was kept constant. Simultaneaously, 2 drops of 1 % potassium permanganate solution was added to the three test tubes.

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When 1% potassium permanganate was added to ethyl alcohol with 6M sulfuric acid and 2 mL water, the solution produced was pink.When 1% potassium permanganate was added to ethyl alcohol with 6M sodium hydroxide and 2 mL water, the solution produced was greenWhen 1% potassium permanganate was added to ethyl alcohol with 2 mL water, the solution produced was pink.

Inference

Comparison of Oxidation Rates of AlcoholsProcedure The samples used were ethanol, isopropyl alcohol, tertbutyl alcohol,

and phenol which are colorless liquids.Potassium dichromate is a yellow solution.Sulfuric acid is a colorless solution.1 mL of samples were placed in different test tubes. The samples are oxidized by adding 6M sulfuric acid and 5 drops of 1% potassium dichromate solution in each of the test tubes simultaneously.

Reaction Involved [O] is potassium dichromate which serves as an oxidizing agent and reduces:

Expected Results When potassium dichromate reduces, a green solution is formed.Primary and secondary alcohols are able to oxidize in the presence of potassium dichromate since they have enough hydrogen atoms attached to the carbon in the hydroxyl group to perform an oxidation reaction. Tertiary alcohols and phenols do not have hydrogen atoms attached to the carbon in the hydroxyl group which means that it cannot be oxidized. Ethanol and isopropyl alcohol will only produce a green product.


When sulfuric acid and potassium dichromate were added to the test solutions, the following changes occurred:

Ethanol and isopropyl alcohol produced a blue green solution. Tertbutyl alcohol produced a yellow orange solution. Phenol produced a cloudy white solution then it turned black

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brown.Inference Ethanol and isopropyl alcohol are primary and secondary alcohols,

respectively.

Ceric Nitrate Test for AlcoholsProcedure The samples used were ethanol, isopropyl alcohol, water, and

tertbutyl alcohol which are colorless liquids.10 drops of sample was added to 1 mL ceric nitrate solution.

Reaction Involved

Expected Results When alcohols react with cerric nitrate, an alkoxy cerium(IV) compound is formed which is indicated by a red product. Ethyl alcohol, isopropyl alcohol, and tertbutyl alcohol should change into a red solution.


When 1 mL ceric nitrate was added to the samples, the following changes happened:

Ethyl alcohol, isopropyl alcohol, and tertbutyl alcohol turned dark orange

Water turned yellowInference Ethyl alcohol, isopropyl alcohol, and tertbutyl alcohol are alcohols.

Chromic Acid test for Distinguishing 10 and 20 alcohols from Tertiary AlcoholsProcedure The samples used were ethanol, isopropyl alcohol, tertbutyl alcohol,

and phenol which are colorless liquids.Chromic acid is a dark yellow solution.Acetone is a colorless liquid.2 drops or 50 mg of sample was added with 1 mL reagent grade acetone and 4 drops of chromic acid.

Reaction Involved

Expected Results When chromic acid oxidizes, it turns into a green solution.Only primary alcohols, secondary alcohols, and phenol are capable of oxidizing chromic acid therefore a change in color should be only observed in ethanol, isopropyl alcohol and phenol.

Experimental When acetone and chromic acid was added to the test samples, the

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Results / Observations following happened: Ethanol produced a yellow brown solution with green and

black precipitates. Tertbutyl alcohol produced a clear orange solution with a small

black immiscible bottom layer. Isopropyl alcohol produced a brown solution with green

precipitate and black immiscible bottom layer. Phenol produced a dark brown solution with brown

precipitates.Inference Ethanol, isopropyl alcohol, and Phenol are primary alcohol, secondary

alcohol, and phenol, respectively.

Lucas Test for Determining 10,20, and 30 alcoholsProcedure The samples used were ethanol, isopropyl alcohol, and tertbutyl

alcohol which are colorless liquids.1 mL of Lucas reagent was added to each of three test tubes. ethanol, isopropyl alcohol, and tertbutyl alcohol were added to the three test tubes then they were covered by a stopper and shaken.

Reaction Involved

Expected Results When the Lucas reagent, containing zinc chloride and hydrochloric acid, is reacted with an alcohol, the alcohol forms a carbocation. The formation of a carbocation, indicated by the formation of an immiscible layer, is easier if it is more stable in that state. By hyperconjugation and inductive effect, tertiary alcohols will produce a carbocation faster then followed by secondary and primary alcohols, respectively. This means that an immiscible layer will occur faster with tertbutyl alcohol then isopropyl alcohol and ethanol, respectively.


When 1 mL of Lucas’s reagent was added to the test samples two immiscible layers formed: a clear bottom layer and a white top layer. Tertbutyl alcohol formed the immiscible layers the fastest followed by isopropyl alcohol then the slowest to form the immiscible layers is ethanol.

Inference Tertbutyl alcohol, isopropyl alcohol, and ethanol are tertiary, secondary, and primary alcohols, respectively.

Acidity of Phenols Procedure The samples used were phenol, acetic acid, and ethyl alcohol. Phenol

is a white wet amorphous solid that easily melts into a clear viscous liquid. Acetic acid and ethanol are colorless liquids.10% sodium bicarbonate solution is a colorless liquid.50 mg or 5 drops of sample was added to 0.5 mL of distilled water. The solution was tested with litmus paper then it was poured to 1 mL of 10% sodium bicarbonate solution.

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When water was added to the sample and tested with litmus paper, the following were observed:

Phenol made red litmus paper into blue which makes it basic Acetic acid made blue litmus paper to red which makes it

acidic Ethanol made blue litmus paper to red which makes it acidic

When 10% sodium bicarbonate was added to the samples, the following changes happened:

Phenol produced a colorless solution with cloudy white precipitates. Bubbles evolved but disappeared.

Acetic acid formed a clear solution with precipitates. Bubbles evolved.

Ethanol formed a colorless solution with no bubbles and no precipitates.

Inference

Reaction of Phenols with Bromine water Procedure The sample used is phenol which is a white wet amorphous solid that

easily melts into a clear viscous liquid.Bromine water is a yellow brown solution.10 drops of bromine water was added to 5 drops of phenol in a test tube.

Reaction Involved

Expected Results When bromine water reacts with phenol, a white precipitate should be

formed. This white precipitate is 2,4,6-tribromophenol. Experimental Results / Observations

When 10 drops of bromine water was added to 5 drops of phenol, the solution produced became milky white with suspended white precipitates.

Inference Phenol reacted with bromine water to produce a white precipitate which is 2,4,6-tribromophenol.

Ferric Chloride test for water soluble Phenols Procedure The samples used were phenol, ethanol, resorcinol, hydroquinone,

acetic acid, and salicylic acid. Ethanol and acetic acid are colorless liquids. Phenol is a white wet amorphous solid that easily melts into a clear viscous liquid. Resorcinol, hydroquinone, and salicylic acid are white crystals.

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Ferric chloride is a yellow solution.A drop of sample was dissolved in 1 mL ethyl alcohol then 4 drops of 1% ferric chloride was added to the solution.

Reaction Involved

Expected Results When phenols are reacted with ferric chloride, a colored complex is produced. The colored complex should either be red, blue, green, or purple. This means that phenol, resorcinol, salicylic acid, and hydroquinone should produce a colored product.


When Ferric chloride and ethanol was added to the samples the following changes happened:

Phenol produced a clear dark green brown solution Ethanol produced a clear yellow solution Resorcinol produced a dark green solution Hydroquinone produced a dark brown solution Acetic acid produced a clear yellow solution Salicylic acid produced a dark purple solution

Inference Phenol, resorcinol, salicylic acid, and hydroquinone are phenols.

Aldehydes & Ketones

Oxidation of Aldehydes with Potassium PermanganateProcedure The samples used were acetone, formaldehyde, cyclohexanone, and

benzaldehyde which are colorless liquids.Potassium permanganate is a purple liquid.5 drops of 1% potassium permanganate was added to 1 mL distilled water and 4 drops or 50 mg sample. When no reaction occurred, of 6M sodium hydroxide was added.


When the samples were oxidized using potassium permanganate and water was added, the following changes happened:

Acetone did not react so 3 drops of 6M sodium hydroxide was added then the solution turned green with brown precipitates.

Formaldehyde produced a red solution then it turned brown and then turned into a colorless solution with precipitates.

Cyclohexanone produced a bright red solution then it turned dark brown.

Benzaldehyde produced a dark red solution then it turned brown with precipitates.

Inference

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2,4 – Dinitrophenylhydrazine test for Aldehydes and KetonesProcedure The samples used were acetone, formaldehyde, cyclohexanone, and

benzaldehyde which are colorless liquids.2,4-Dinitrophenylhydrazine is an amber solution1 mL of 2,4-Dinitrophenylhydrazine was added with 2 drops or 25 mg of sample.

Reaction Involved

Expected Results When an aldehyde or ketone reacts with 2,4-Dinitrophenylhydrazine, through a nucleophilic attack, a precipitate forms. This precipitate is dinitrophenylhydrazone. If a red dinitrophenylhydrazone forms then the aldehyde or ketone is aromatic if not, the dinitrophenylhydrazone is yellow. Acetone, cyclohexanone, formaldehyde, and benzaldehyde should form yellow precipitates.


When 2,4-Dinitrophenylhydrazine was added to the samples, the following changes happened:

Acetone produced a yellow orange solution with fine precipitates.

Cyclohexanone produced a yellow solution with fine yellow precipitates.

Formaldehyde produced a yellow solution with fine precipitates.

Benzaldehyde produced a yellow orange solution with large yellow precipitates.

Acetic acid produced a yellow solution Ethanol produced a yellow solution

Inference Acetone, cyclohexanone, formaldehyde, and benzaldehyde are aldehydes and ketones.Acetic acid and ethanol are not aldehydes and ketones.

Schiff’s test for Aldehydes Procedure The samples used were acetone, formaldehyde, cyclohexanone, and

benzaldehyde which are colorless liquids.Schiff’s reagent is a green pink solution.4 drops or 50 mg of sample was added to 1 mL of Schiff’s reagent.

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Reaction Involved

Expected Results Schiff’s reagent only reacts with aldehydes. When aldehydes react with the Schiff’s reagent, a bright purple product is formed. Formaldehyde and benzaldehyde should form a bright purple product.


When 1 mL Schiff’s reagent was added to the samples, the following happened:

Acetone did not react since there was no change observed in the solution

Formaldehyde produced a yellow solution which turned purple.

Benzaldehyde produced a yellow solution which became pale yellow with pink precipitates and an immiscible pink top layer.

Inference Formaldehyde and benzaldehyde have aldehyde functional group.

Tollen’s test for Aldehydes Procedure The samples used were acetone, formaldehyde, cyclohexanone, and

benzaldehyde which are colorless liquids.Tollen’s reagent is a colorless solution with white suspended particles.4 or 50 mg of sample was added to Tollen’s reagent in a test tube. When no reaction occurred, the test tube was heated until 60oC.

Reaction Involved

Expected Results When Tollen’s reagent is reacted with an aldehyde, the Tollen’s

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reagent is reduced to silver metal which is indicated by the formation of a metallic black precipitate. Formaldehyde and benzaldehyde should form metallic black precipitates.


When Tollen’s reagent was added to the sample, the following changes happened:

Acetone produced a black solution with a solid and precipitates.

Formaldehyde produced a dark green solution with precipitates.

Cyclohexanone produced a black solution with precipitates. Benzaldehyde formed a black solution with a solid and

precipitates.Inference Impurities in the reagents or samples have altered the result to be less

accurate which made cyclohexanone and acetone precipitate silver metal. The aldehydes should be benzaldehyde and formaldehyde.

Fehling’s test for Distinguishing Aromatic from Aliphatic Aldehydes Procedure The samples used were acetone, formaldehyde, cyclohexanone,

benzaldehyde, and glucose (dissolved in water) which are colorless liquids.Fehling’s solutions A and B form a dark blue solution.1 mL of each Fehling’s solution A and B were mixed to create a dark blue solution then it was mixed with 4 drops or 50 mg of sample then the test tube was heated by a water bath.

Reaction Involved RCHO + 2Cu2+ + 2H2O ==> RCOOH + Cu2O + 4H+

Expected Results Only aldehydes react with Fehlings solution to reduce copper (II) to copper (I). The reduction reaction is indicated by the formation of brown or brick red precipitates which are insoluble Cu2O. Formaldehyde, benzaldehyde, and glucose should produce brick red precipitates.


The following happened when 4 drops of sample was added to 2 drops each of Fehling’s solution A and B:

Acetone produced a transparent blue solution. Cyclohexanone produced two immiscible layers: a clear top

layer and a transparent blue bottom layer. Formaldehyde produced a transparent blue solution. Benzaldehyde produced a milky blue solution with bubbles on

the surface . Glucose produced a transparent blue solution.

The following happened when the solution containing Fehling’s solution A and B and the sample are heated:

Acetone remained transparent blue Cyclohexanone remained having two immiscible layers: a clear

top layer and a transparent blue bottom layer. Formaldehyde produced a blue green solution with brown

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orange precipitates. Benzaldehyde remained milky blue but with green yellow

precipitates. Glucose remained transparent blue but with red violet

precipitates.Inference Formaldehyde, benzaldehyde, and glucose formed precipitates so they

have aldehyde functional group.

Reaction with Sodium Bisulfite for Aldehydes and Aliphatic methyl Ketone Procedure The samples used were acetone, formaldehyde, cyclohexanone, and

benzaldehyde which are colorless liquids.Sodium Bisulfite is a colorless liquid. 4 drops or 50 mg of sample was added to 1 mL sodium bisulfite solution then it was shaken. It was left to stand for 2 minutes.

Reaction Involved

Expected Results When a ketone reacts with sodium bisulfite, a precipitate is formed. If the ketone is a methyl ketone, no precipitate is formed. This means that only cyclohexanone should form a precipitate.


When sodium bisulfite was added to the samples, the following happened:

Acetone did not react since no changes were observed. Benzaldehyde produced two immiscible layers. Cyclohexanone temporarily produced an oily cloudy white

solution then it separated into two immiscible layers. Formaldehyde did not react since no changes were observed.

Inference Cyclohexanone is a ketone but not a methyl ketone.

Chromic Acid test for Aldehydes Procedure The samples used were acetone, formaldehyde, cyclohexanone, and

benzaldehyde which are colorless liquids.Chromic acid is a dark yellow solution.1 mL of acetone was added to 2 drops or 25 mg of sample and 5 drops of chromic acid.

Reaction Involved

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Expected Results When chromic acid oxidizes, it turns into a green solution.Chromic acid oxidizes in aldehydes faster compared to ketones.Banzaldehyde and formaldehyde will form a green solution faster than acetone and cyclohexanone.


The following happened when chromic acid and acetone was added to the samples:

Acetone did not react since no changes were observed. Benzaldehyde produced a dark brown (coffee-like) solution

and it released heat (exothermic). Cyclohexanone produced two immiscible layers: an orange top

layer and a black bottom layer. Formaldehyde produced a dark brown solution and it released

heat (exothermic).Inference Benzaldehyde and Formaldehyde are aldehydes while Cyclohexanone

and acetone are ketones.

Carboxylic acid & Acid derivatives

Oxidation with Potassium Permanganate

Procedure The samples used are acetic acid, lactic acid, benzoic acid, and succinic acid. Acetic acid and lactic acid are colorless liquids. Benzoic acid is a white crystalline solid so it was dissolved in ethanol. Succinic acid is a white crystalline solid so it was dissolved in water.1% potassium permanganate is a purple solution.5 drops of sample was added to 5 mL 1% potassium permanganate solution then the mixture was heated using a water bath.


After adding 1% potassium permanganate solution and heating in a water bath, the following changes happened:

Acetic acid did not react since no change was observed Lactic acid produced a clear brown solution with brown

precipitates. Benzoic acid produced a dark chocolate brown solution. Succinic acid produced a light chocolate brown solution.

Inference

Esterification Procedure The sample used is salicylic acid which is a white crystalline solid.

Methanol and sulfuric acid are colorless liquids.50 mg salicylic acid was placed in a test tube then, 2 mL of methanol and 10 drops of concentrated sulfuric acid was added. The mixture was heated using a water bath then cooled to room temperature.

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Reaction Involved

Expected Results When salicylic acid is reacted with excess methanol, the carbonyl group in salicylic acid becomes more electrophilic. This makes it bond to another hydrocarbon group thus creating an ester. The presence of an ester is indicated by a fruity odor. The final product of the esterification should smell fruity.


When methanol and sulfuric acid was added to salicylic acid and after heating and cooling the solution in a water bath, the solution produced was odorless and was forming bubbles.

Inference The final product should smell fruity but due to personal errors the odor was not able to be observed.

Salt formation Procedure The samples used are acetic acid, lactic acid, benzoic acid, and

succinic acid. Acetic acid and lactic acid are colorless liquids. Benzoic acid is a white crystalline solid so it was dissolved in ethanol. Succinic acid is a white crystalline solid so it was dissolved in water.Zinc metal is a gray and fine powder.A pea size of zinc metal was added to a test tube containing 1 mL of sample.


When Zinc metal was added to the sample, the following changes happened:

Fine zinc metal separated from acetic acid. Bubbles formed at the surface of the zinc metal and some zinc metal stocked to the walls of the test tube.

Zinc metal did not separate from lactic acid. The mixture produced was viscous liquid. Gray wet crystals formed at the sides of the test tube and bubbles formed at the surface of the mixture.

Fine zinc metal settled and formed a circle. It separated from Benzoic acid.

Granulated zinc metal formed and separated from succinic acid and bubbles formed at the surface of the zinc metal.

Inference

Schotten-Bauman Reaction: Formation of Ester from Acyl Halide and AlcoholsProcedure Ethyl alcohol and 20% sodium hydroxide are colorless liquids.

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Benzoyl chloride is a colorless to light yellow liquid.1 mL of ethyl alcohol and 2 mL of water was mixed in a test tube. 5 drops of benzoyl chloride was added to the mixture while shaking then 3 mL of 20% sodium hydroxide was also added.

Reaction Involved

Expected Results

Acyl halides react with alcohols in basic condition to form an ester which is immiscible in water and less dense than water. The formation of an ester using benzoyl chloride, an acyl halide, and ethyl alcohol with sodium hydroxide is indicated by the formation of an immiscible layer and a sweet odor.


After shaking and adding ethyl alcohol, 20% sodium hydroxide, and benzoyl chloride, the solution turned viscous with tiny bubbles. After a few minutes, it formed two immiscible clear layers. The odor of the mixture was sweet and minty.

Inference An ester was formed by reacting benzoyl chloride, an acyl halide, and ethyl alcohol with sodium hydroxide.

Alkaline Iron (III) Hydroxamate test for Carboxylic Acid Procedure Ethyl acetate, hydroxylamine hydrochloride in ethanol, and sodium

chloride are colorless liquids.10% Iron (III) chloride is a green black solution.2-3 drops of ethyl acetate was added to 1 mL of 5% hydroxylamine hydrochloride in ethanol then, 4 drops of 5% sodium chloride solution was added and the mixture was heated to boiling using a water bath. When the test tube cooled, 2 mL of 1M hydrochloric acid was added. When cloudliness develops, add 2 mL of ethanol. After, 10% iron (III) chloride was added dropwise while swirling.

Reaction Involved

Expected Results When esters react with hydroxylamine in basic solution, it forms hydroxamic acid that will react to ferric chloride which will form bluish red hydroxamates. In using ethyl acetate, the product formed should be bluish red in color.


When ethyl acetate, hydroxylamine hydrochloride in ethanol, and sodium chloride solution were mixed and heated, the solution produced was colorless.When 10% Iron (III) chloride was added, the solution produced was yellow and it had an oily dispersed appearance.

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No ethanol was added since the solution was not cloudy after cooling.Inference Impurities in the reagents or samples have altered the result to be less

accurate which diluted the product formed. Ethyl acetate is an ester.

Amines

Basicity of AminesProcedure The solutions used were methylamine, diethylamine, triethylamine,

and aniline. Methylamine is a colorless liquid. Diethylamine is a dark orange liquid. Triethylamine is a light yellow liquid. Aniline is a dark brown liquid. Phenolphthalein is a colorless liquid.Bromothymol blue is a blue liquid.2 drops or 25 mg of sample was added to each two test tubes. One test tube was added with 1 drop of phenolphthalein and the other test tube was added with 1 drop of bromothymol blue.


When phenolphthalein was added to the samples, the following happened:

Methylamine changed from clear to a purple solution. Diethylamine did not react since no change was observed. Triethylamine Aniline changed form an oily red solution to an oily red brown

solution.When bromothymol blue was added to the samples, the following happened:

Methylamine changed from clear to a dark blue solution. Diethylamine changed form a yellow to a dark blue solution. Triethylamine changed from a clear to a dark blue solution

with emulsions at the sides. Aniline changed form an oily red solution to a blue solution

with oily brown red emulsions at the surface. Inference

Salt formation Procedure The samples used were methylamine, diethylamine, triethylamine,

and aniline. Methylamine is a colorless liquid. Diethylamine is a dark orange liquid. Triethylamine is a light yellow liquid. Aniline is a dark brown liquid. Hydrochloric acid is a colorless liquid.1 mL of concentrated hydrochloric acid was added with 5 drops of sample. After, the mixture was cooled using a cold water bath then 2

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mL of distilled water was added to the resulting mixture.Reaction Involved

R - NH2 + HCI —→ RNH3 CI Alkylammonium Chloride

Expected Results Experimental Results / Observations

When hydrochloric acid was added to the samples, the following changes were observed:

Methylamine produced a colorless liquid. Diethylamine produced a cloudy light orange solution. Triethylamine produced two immiscible layers: the top layer

was cloudy white and the bottom layer was colorless. Aniline produced a cloudy white solution with red

coagulations.When the samples with hydrochloric acid were cooled, the following changes were observed:

Methylamine did not change. Diethylamine did not change. Triethylamine did not change. Aniline became a white solution with red coagulations.

When distilled water was added to the samples, the following changes were observed:

Methylamine did not change. Diethylamine became a lighter orange solution (diluted). Triethylamine still had two immiscible layers but with some

changes: the top layer became whiter and the bottom layer was added.

Aniline became a colorless solution with red coagulations.Inference

Effect of Amino group in substitution in the Benzene ring Procedure The sample used is aniline which is a dark brown liquid.

Bromine water is a yellow brown solution.3 drops of aniline and 2 mL of water were mixed inside a test tube then, bromine water was added dropwise.

Reaction InvolvedExpected Results Experimental When water and bromine water was added to aniline, a clear solution

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Results / Observations was formed with brown bubbles then it became a cloudy white solution with dark brown bubbles and a light brown big bubble in the middle of the solution. Fumes evolved.

Inference

Oxidation of Aniline with Potassium PermanganateProcedure The samples used were methylamine, diethylamine, triethylamine, and

aniline. Methylamine is a colorless liquid. Diethylamine is a dark orange liquid. Triethylamine is a light yellow liquid. Aniline is a dark brown liquid. 1% potassium permanganate is a purple solution.In 4 drops or 50 mg of sample, 1 mL of water and 1% potassium permanganate solution was added. After, the mixture was shaken.


When water and 1% potassium permanganate solution was added to the samples, the following were observed:

Methylamine produced a colorless solution which turned into a light brown solution with brown precipitates.

Diethylamine produced a dark orange solution then formed brown precipitates.

Triethylamine produced a light yellow solution with two immiscible layers: the top layer was cloudy white and the bottom layer was dark brown.

Aniline produced an amber solution which turned into a dark brown solution with brown precipitates.

Inference

Quinhydrone test Procedure The samples used were methylamine, diethylamine, triethylamine,

and aniline. Methylamine is a colorless liquid. Diethylamine is a dark orange liquid. Triethylamine is a light yellow liquid. Aniline is a dark brown liquid. Quinhydrone is a green solution.2 drops or 25 mg of sample was added to 6 mL of water in a test tube. After, a drop of 5% Quinhydrone in methanol solution was added then the mixture was shaken and left standing for 2 minutes.


When water was added to the samples, the following were observed: Methylamine dissolved. Diethylamine dissolved. Triethylamine dissolved. Aniline did not dissolve and formed brown oily balls.

22

When quinhydrone solution was added to the samples, the following were observed:

Methylamine produced a colorless solution which turned purple.

Diethylamine produced a colorless solution which turned light brown.

Triethylamine produced a colorless solution which turned medium brown.

Aniline produced a colorless solution which turned dark brown.

Inference

http://www2.ucdsb.on.ca/tiss/stretton/CHEM2/orglab1.htm

http://www.tutorvista.com/content/chemistry/chemistry-iii/hydrocarbons/alkynes-chemical-properties.php

http://www.docbrown.info/page04/OilProducts05.htm

http://www.wellesley.edu/Chemistry/chem211lab/Orgo_Lab_Manual/Appendix/ClassificationTests/unsaturation.html#Bromine

http://faculty.swosu.edu/william.kelly/pdf/qo4.pdf

http://www.docbrown.info/page13/ChemicalTests/ChemicalTestsf.htm

http://phoenix.liu.edu/~nmatsuna/che122/exp13.pdf

http://www.chemguide.co.uk/organicprops/phenol/ring.html

http://www.chemistry.ccsu.edu/glagovich/teaching/316/qualanal/tests/ceric.html

http://www.wsc.ma.edu/cmasi/organic_lab/organic1_lab/esterification_salicylic_acid.pdf

http://www.wsc.ma.edu/cmasi/organic_lab/organic1_lab/esterification_salicylic_acid.pdf

http://www.chemistry.ccsu.edu/glagovich/teaching/316/qualanal/tests/ceric.html

http://www.chemguide.co.uk/organicprops/phenol/ring.html

http://phoenix.liu.edu/~nmatsuna/che122/exp13.pdf

http://www.docbrown.info/page13/ChemicalTests/ChemicalTestsf.htm

http://faculty.swosu.edu/william.kelly/pdf/qo4.pdf



http://www.docbrown.info/page04/OilProducts05.htm



http://www2.ucdsb.on.ca/tiss/stretton/CHEM2/orglab1.htm

10-14 functional group analysis

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