Practical Organic Chemistry (Created and Owned by- Science Mania)

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Practical Organic Chemistry (Created and Owned by- Science Mania) by Mind Map: Practical Organic Chemistry (Created and Owned by- Science Mania)

1. Detection of HydrocarbonHydrocarbon

1.1. Liebig’s Method

1.1.1. Carbon

1.1.1.1. C + CuO ⟶ CO2 CO2 + Ca(OH)2 ⟶ CaCO3 Excess H2O + CO2 + CaCO3 ⟶ Ca(HCO3)2

1.1.1.1.1. On passing carbon dioxide through lime water, it turn milkiness due to CaCO3 but on excess of CO2, milkiness disappear

1.1.2. Hydrogen

1.1.2.1. H + CuO ⟶ H2O CuSO4 + H2O ⟶ CuSO4.5H2O

1.1.2.1.1. Water turn anhydrous copper sulphate white to Blue

2. Alcohol

2.1. 1. Sodium Test

2.1.1. When Na-metal reacts with alcohol H2(g) evolve. It occurs in 1, 2 & 3 degree alcohols

2.2. 2. Ceric Ammonium Nitrate Test (CAN Test) :

2.2.1. Positive Test: Color changes from yellow to red first then to colorless solution. (1 min to 12 hrs)

2.2.1.1. (NH4)2[Ce(NO3)6] + 3ROH→ [Ce(NO3)4(ROH)3] + 2NH4NO3

2.2.2. Very good test for Primary, secondary alcohol, but slow for tertiary alcohol

2.2.3. Note: Phenols gives brown or black products.

2.3. 3. Jones Oxidation Test

2.3.1. CrO3 in acidic medium ( Chromic anhydride)

2.3.1.1. A positive test for 1, and 2 degree alcohols consists in the changes from an orange-red color (CrO3) to green colour (Cr2(SO4)3) in 2 sec.

2.3.1.2. Tertiary alcohols give no visible reaction

2.4. 4. Lucas Test

2.4.1. This test distinguishes 1, 2 & 3 degree alcohol from each other It uses, anhydrous ZnCl2 in Conc. HCl (lucas reagent)

2.4.1.1. ➔ 3 degree alcohols give White turbidity solution immediately ➔ 2 degree alcohols give White turbidity solution within 5 to 10 minutes ➔ 1degree alcohols does not give white turbidity at normal temperature

2.4.2. Important Note- All carbocation stabilized by resonance, aromatic and back-bonding also give white turbidity solution quickly

2.4.2.1. In lucas Test, SN1 Mechanism is followed.

2.5. 5. Victor Meyer Test

2.5.1. This test distinguishes 1, 2 & 3 degree alcohol (RBC test)

2.5.1.1. 1 degree alcohols give red color on reaction with Red P+I2 followed by AgNO2, then HNO2 and finally NaOH

2.5.1.2. 2 degree alcohols give Blue color on reaction with Red P+I2 followed by AgNO2, then HNO2 and finally NaOH

2.5.1.3. No color visible with 3 degree alcohol

2.6. 6. Iodoform Test

2.6.1. Ethanol and secondary alcohols which contain CH3—CH(OH)R group (iodoform reaction) give positive iodoform test

2.6.1.1. NaOCl oxidises CH3—CH(OH)R group to CH3COR group and then iodinates it in the alkaline medium of the reaction mixture by replacing the α-hydrogen attached to the carbon atom adjacent to carbonyl group by iodine. Iodoform is formed after cleavage of C—C bond.

3. Vicinal Diol

3.1. 1. Periodic Test (Malparade Oxidation)

3.1.1. When vic-diol is allowed to be oxidised by Periodic Acid, then Periodic acid (HIO4) is reduced to Iodic Acid (HIO3) (Oxidation state of iodine decrease from +7 to +5

3.1.2. Then Iodic Acid is treated with AgNO3 giving white precipitate of AgIO3 (Silver Iodate) which confirm presence of Vic-Diol.

3.1.3. Important Note- Olefins, 2o alcohols, 1, 3 - glycols, ketones and aldehydes are not affected by HIO4 condition

4. Aldehyde and ketone

4.1. 1. 2,4-DNP Test

4.1.1. Positive Test: Formation of yellow, orange or red ppt The precipitate may be oily at first and become crystalline on standing

4.1.2. Aldehyde + 2,4-Dnitrophenylhydrazine ⟶ 2,4-Dinitrophenylhydrozone

4.2. 2. Sodium Bisulphite Test

4.2.1. Positive Test: By aldehydes and methyl ketone

4.2.2. Reaction of aldehyde/ Methyl Ketone with Bisulphite give white crystalline of adduct

4.3. 3. Iodoform

4.3.1. Positive Test: Yellow precipitate for methyl ketones

4.3.1.1. RCOCH3 + I2/NaOH ⟶ (RCOO-) + CHI3

4.3.2. Some compounds that can be easily oxidized to methyl ketones give also positive results Example- Ethanol, propan-2-ol etc can also give positive iodoform

4.4. 4. Tollen's Reagent

4.4.1. Positive for Aldehyde, alpha-hydroxy-Ketone but negative for ketone

4.4.1.1. Positive Test : Formation of silver mirror (Ag(s)) or colloidal (granular) Gray or black Ag precipitate

4.4.1.2. RCOH + Ag(NH3)OH ⟶ Ag + (RCOO-NH4+)

4.4.2. Reagent Used- Ag(NH3)2OH

4.4.2.1. Important Note- Phenyl hydroxylamine, formic acid, formyl ester, formyl chloride, ethylene chloride, hemiacetal, haloform also give positive tollen test

4.5. 5. Benedict Reagent

4.5.1. Positive for all aldehyde, alpha-hydroxy-ketone but negative for aromatic aldehyde and ketone

4.5.1.1. Positive Test : yellow or yellowish green/reddish ppt.

4.5.2. Reagent Used- sodium citrate, sodium carbonate, and the pent hydrate of copper(II) sulfate

4.5.2.1. Cu2+ (blue) get reduced to cuprous ion (Cu+)( brick red color)

4.6. 6. Fehling Solution

4.6.1. Positive Test give by aldehyde having atleast one alpha hydrogen and alpha-hydroxy-ketone

4.6.1.1. Positive test- Red precipitate of Cu2O

4.6.2. Reagent Used- Alkaline solution of sodium potassium tartrate and Pentahydrate of copper(II) sulphate

4.6.2.1. CuO + RCOH ⟶ Cu2O + RCCO-

4.6.2.2. Important Note-Phenyl hydroxyl amine, hydroxyl amine, haloform, formic acid, benzoin, furoin also give positive fehling test

4.6.2.2.1. Important Note- Glyoxalic Acid, methyl-glyoxal, glyoxal, furfural, piconaldehyde, benzil, hemiacetal, furil, acetal, hemiketal, ketal give negative tollens test.

4.7. 7. Jones Oxidation Test

4.7.1. CrO3 in acidic medium ( Chromic anhydride)

4.7.1.1. A positive test for aldehyde and ketone consists in the changes from an orange-red color (CrO3) to green colour (Cr2(SO4)3) in 2 sec.

4.8. 8. Schiff Test

4.8.1. Aldehydes also give pink colour with Schiff’s reagent (this reagent is prepared by decolourising aqueous solution of p–rosaniline hydrochloride dye by adding sodium sulphite or by passing SO2 gas).

4.8.2. Ketones do not respond to this test.

5. Alkene and Alkynes

5.1. 1. Bromine Water Test

5.1.1. Positive Test : It decolorize the red color of Bromine water without of gas (HBr)

5.1.1.1. Alkenes & alkynes give positive results

5.1.2. Important Note- If HBr is evolved, it indicates phenols, enols & enolizable compounds

5.2. 2. Baeyer Test (KMnO4)

5.2.1. Alkene, alkynes, aldehyde and alcohol give positive test

5.2.1.1. Positive Test: Purple color discharges, and brown color ppt (MnO2) appears

6. Terminal Alkyne

6.1. 1. Sodium Test

6.1.1. Reaction of terminal alkynes with Na metal will give hydrogen gas

6.2. 2. Sodamide(NaNH2)/Potamide Test (KNH2) Test

6.2.1. Sodamide is strong base ( a.k.a Piranha Base) so terminal alkyne will evolve ammonia gas. When ammonia gas react rod dipped in HCl, it give white fumes.

6.3. 3. Tollen Reagent

6.3.1. It will give white precipitate

6.3.2. Tollen Reagent -[Ag(NH3)2]OH

6.4. 4. Ammonium cuprous chloride Test

6.4.1. It will give red precipitate

6.4.1.1. CH≡CH + CuCl2⟶ (-C≡C-) + 2 (Cu+)

6.4.2. Reagent- CuCl2 + NH4OH

7. Alkyl Halide

7.1. 1. Ethanolic Silver Nitrate Test

7.1.1. SN1 Mechanism is followed

7.1.1.1. Positive Test: formation of ppt indicates 2° and 3° R-X and carbocation stabilized by resonance, aromaticity and back bonding give positive result

7.1.1.1.1. 1° RX, Ar-X, and vinyl halides give negative Result.

7.1.2. The reaction of alkyl halide with silver nitrate yields a silver halide precipitate and R-O-N-O2

7.2. 2. Sodium Iodide Test in acetone

7.2.1. The Nal test can be used to test for the presence of bromine or chlorine. Sodium halide (NaX) precipitates from the solution.

7.2.1.1. R-X + NaI ⟶ R-I + NaX (ppt)

7.2.2. SN2 Mechanism is followed

8. Carboxylic acids

8.1. 1. Litmus test

8.1.1. Carboxylic acid have acidic nature will turn blue litmus to red

8.2. 2. Sodium hydrogencarbonate test

8.2.1. Compound having carboxylic acid and sulfonic acid on reaction with NaHCO3 will give carbon dioxide gas.

8.2.1.1. Important Note- Para-Nitro phenol, 2,4-dinitro-phenol and Picric acid will also give carbon dioxide gas on reaction with NaHCO3.

8.2.2. RCOOH + NaHCO3 → RCOONa + H2O + CO2

8.3. 3. Ester test

8.3.1. Acid on reaction with alcohol in acidic medium will give fruity sweet like smell Ester

8.3.1.1. RCOOH + R'OH ⟶ RCOOR' + H2O

8.4. 4. Neutral FeCl3 Test

8.4.1. Acetic Acid and Formic acid will give red color with Neutral FeCl3

8.4.1.1. FeCl3 + RCOOH ⟶ (ROO)3Fe + HCl + CH2=CH2

8.4.2. Salicylic Acid will give violet color on reaction with Neutral FeCl3

8.4.3. Succinic acid and Benzoic Acid will buff (light brown color) with Neutral FeCl3

8.4.4. Oxalic, tartaric, citric, and lactic acid will give no color with Neutral FeCl3.

9. Numerical Method of Estimation of Some Important Element

9.1. https://drive.google.com/file/d/1YynMi-MzWcbxDPaKyOI8cxIOvXtlKYkZ/view?usp=sharing

10. Purification of Organic Chemistry (NEW)

10.1. Examples

10.1.1. Sublimation

10.1.1.1. NaCl + Napthalene

10.1.2. Crystallization

10.1.2.1. Napthalene + Benzoic Acid

10.1.2.2. NaCl + Glucose

10.1.3. Simple Distillation

10.1.3.1. Chloroform + Aniline

10.1.4. Fractional Distillation

10.1.4.1. Separating fractions of crude oil

10.1.4.2. Kerosene + Napthalene

10.1.4.3. n-Hexane + n-Pentane

10.1.5. Distillations under reduced pressure

10.1.5.1. Glycerol + Spent Dye

10.1.6. Steam Distillation

10.1.6.1. Aniline + Water

10.1.7. Differential Extraction

10.1.7.1. H20 + CH2Cl2

10.1.7.2. Any organic compound in Water

10.2. Definition and Difference

10.2.1. https://dochub.com/m/shared-document/mishra-d-daksh2003/8adOrbPVQEoPv2MV24Mj7D/c993f75e-c014-4164-8ba1-223392a47856-jpg?dt=skdY5bGrPweVK9xL7aS3

11. If Both nitrogen and sulphur is present

11.1. C + N +S+ Na ⟶ NaCN (Lassaigne extract) (SCN-)+ FeCl3 ⟶ Fe (SCN)3 (blood red color)

11.2. NaSCN + HCl ⟶ NaCl+ HSCN CoCl3 + HSCN ⟶ H2[Co(SCN)4] (Blue)

12. Nitrogen

12.1. Lassaigne test

12.1.1. C + N + Na ⟶ NaCN (Lassaigne extract) CN- + Fe2+ ⟶ [Fe (CN)6]4- [Fe (CN)6]4- + Fe3+ + xH2O ⟶Fe4[Fe(CN)6]3.xH2O

12.1.1.1. Give Prussian blue color

12.1.1.1.1. Important Note- For detection of nitrogen in compound having lesser amount of carbon (for e.g.- Urea), sometime we add naphthalene, anthracene, xylene, mesitylene which help in formation of more cyanide ions.

13. Sulphur

13.1. The sodium fusion extract is acidified with acetic acid and lead acetate is added to it. A black precipitate of lead sulphide indicates the presence of sulphur.

13.2. On treating sodium fusion extract with sodium nitroprusside, it show appearance of violet colour further indicates the presence of sulphur.

13.2.1. Na2S + Na2[Fe(CN)5NO] ⟶ Na4[Fe(CN)5NOS]

14. Halogen

14.1. The sodium fusion extract is acidified with nitric acid and then treated with silver nitrate.

14.1.1. A white precipitate, soluble in ammonium hydroxide

14.1.1.1. It confirm Chlorine

14.1.2. A yellowish precipitate, sparingly soluble in ammonium hydroxide

14.1.2.1. It confirm Bromine

14.1.3. A yellow precipitate, insoluble in ammonium hydroxide

14.1.3.1. It Confirm Iodine

15. Phosphorus

15.1. The solution is boiled with nitric acid and then treated with ammonium molybdate. A yellow colouration or precipitate indicates the presence of phosphorus.

15.1.1. Na3PO4 +HNO3⟶ H3PO4 + NaNO3 H3PO4 + (NH4)MoO4 ⟶ (NH4)PO4.12MoO3↓ (Yellow ppt)

16. Amine

16.1. 1. Nitrous Acid Test

16.1.1. Reaction of amines with nitrous acid (HONO) classifies the amine not only as 1°, 2°, or 3°, but also as aliphatic or aromatic.

16.1.1.1. 1°

16.1.1.1.1. Aliphatic amine

16.1.1.1.2. Aromatic amine

16.1.1.2. 2°

16.1.1.2.1. 2° amines undergo a reaction with nitrous acid to form N-nitrosamine, which are usually yellow solids.

16.1.1.3. 3°

16.1.1.3.1. Aliphatic Amines

16.1.1.3.2. Aromatic Amines

16.2. 2. Hinesburg Test

16.2.1. Based on the reaction of the amine with benzenesulfonyl chloride (Hinsberg reagent), it can be used to separate 1, 2, and 3 degree amines.

16.3. 3. Libermann's nitroso test

16.3.1. It is used as a test for secondary amines. Secondary amines (aliphatic as well as aromatic) reacts with nitrous acid to form N-nitrosamines.

16.3.1.1. Nitrosamines are water soluble yellow oils and when warmed with phenol and few drops of conc.sulphuric acid, produce a green colour solution which turns blue on adding alkali. This reaction is called Libermann's nitroso reaction.

16.3.1.1.1. R2NH + HNO2 ⟶ R2-N-N=O R2-N-N=O + Phenol in H2SO4 ⟶ Green color

16.3.2. Tertiary amine do not react with nitrous acid.

16.4. 4. Sodium metal test

16.4.1. The active hydrogen on 1° and 2° amines undergo reaction with sodium to form salt and liberate hydrogen gas

16.5. 5. Carbyl- Amine Test

16.5.1. When aliphatic/aromatic primary amines are heated with chloroform and alcoholic KOH, foul smelling carbylamines ( or isocyanides) are obtained. This test is not given by secondary or tertiary amines.

16.5.1.1. R-NH2 + CHCl3 + KOH⟶ R-NC + KCl

16.6. 6. Azo-dye test

16.6.1. a primary aromatic amine reacts with nitrous acid, which is generated by the reaction of NaNO2 and HCl at 0–5°C to produce a diazonium salt. The diazonium salt couples with beta naphthol to make a scarlet red dye slightly soluble in water.

16.6.1.1. 4-Hydroxybenzene- Orange

16.6.1.2. 4-aminobenzene- Yellow

16.6.1.3. 4-nitrophenylazoresorcinol - violet

16.6.1.4. Methyl orange- red in acidic and yellow in basic

16.6.1.5. Methyl yellow- yellow

16.6.1.6. Paranitroaniline- Brilliant red color

16.6.1.7. Phenolpthalein- pink in basic and colorless in acidic

16.7. 7. Solutbility Test [HCl Test]

16.7.1. Take 1 mL of given organic compound in a test tube and add a few drops of dilute HCl to it. Shake the contents of the test tube well. If the organic compound dissolves, it shows the presence of an amine

16.7.1.1. C6H5NH2 + HCl → [C6H5NH3+]Cl-

17. Phenol

17.1. 1. Sodium Metal Test

17.1.1. As with alcohols, the acidic hydrogen in phenol can be detected with sodium

17.2. 2. Cerric Ammonium nitrate Test (CAN Test)

17.2.1. Phenols undergo reaction with yellow ceric ammonium nitrate to produce brown or black products.

17.3. 3. KMnO4 Test

17.3.1. Phenols reduce potassium permanganate solution and undergo oxidation to quinones.

17.3.1.1. Mn7+ (purple) get reduced to Mn4+ (brown)

17.4. 4. Bromine water test

17.4.1. Positive Test: decolorization of bromine water .

17.5. 5. Neutral FeCl3 Test

17.5.1. Phenol+ FeCl3 give violet color

17.5.1.1. Resorcinol, o–, m– and p–cresol give violet or blue colouration, catechol gives green colour which rapidly darkens. 1 and 2–Naphthol do not give characteristics colours

17.5.2. 6C6H5OH + FeCl3 → [Fe(C6H5O)6]3– (Violet complex) + 3HCl + 3H+

17.6. 6. Libermann’s nitroso test

17.6.1. While phenol is reacted with NaNO2 and concentrated H2SO4 ,it provides a deep green colour which changes to red on dilution with water. while generated alkaline along with NaOH, blue colour is restored.

17.7. 7. Phthalein dye test

17.7.1. Phenols condense with phthalic anhydride in the presence of concentrated H2SO4, to give phenolphthalein which gives a dark pink colour with NaOH solution. This is called phthalein dye test.

17.7.1.1. m-cresol

17.7.1.1.1. Bluish Purple

17.7.1.2. o-cresol

17.7.1.2.1. Red

17.7.1.3. p-cresol

17.7.1.3.1. No color

17.7.1.4. Catechol

17.7.1.4.1. Blue

17.7.1.5. Resorcinol

17.7.1.5.1. Green fluorescent colour of fluorescein

17.8. 8. Iodoform Test

17.8.1. Phenol, Catechol,quinol fail to give iodoform test

17.8.2. Resorcinol, Phloroglucinol give positive iodoform test

18. Alpha-Amino Acid (Protein)

18.1. 1. Ninhydrin Test

18.1.1. Ninhydrin is a powerful oxidizing agent and reacts with amino-acid to give a blue-violet compound

18.1.1.1. Note : Ammonia, primary amines, amoniacids and peptides also react with ninhydrin.

18.2. 2. Xanthoproteic reaction

18.2.1. Amino-acid or protein having aromatic group , undergo nitration on heating with concentrated nitric acid. The salts of these derivatives are orange or yellow in colour.

18.3. 3. Biuret test for peptide bonds

18.3.1. Alkaline copper sulphate reacts with compounds containing two or more peptide bonds to form complexes of violet colour.

18.3.1.1. Important Note- The reaction is not absolutely specific for peptide bond because many compounds containing two carbonyl groups linked through nitrogen or carbon atoms give a positive result.

19. Carbohydrate

19.1. 1. Molisch’s test

19.1.1. All carbohydrate will give positive molisch test

19.1.2. Molisch’s reagent: 5% alpha-naphthol solution in ethyl alcohol

19.1.3. To solution, add molisch reagent followed by adding few drop of conc. sulphuric acid will give a violet colored ring at junction of two liquid. The violet ring indicates the presence of carbohydrates in the solution.

19.2. 2. Benedict Test

19.2.1. All monosaccharides and disaccharides except sucrose give positive Benedict’s test. This test is negative for polysaccharides

19.2.2. Benedict reagent- Copper Sulfate, Sodium Carbonate, Sodium Citrate

19.2.3. The precipitates of cuprous oxide (brick-red color) indicate the presence of a reducing sugar in the test tube.

19.3. 3. Iodine Test

19.3.1. This test is specific for polysaccharides only

19.3.2. Iodine Reagent: 0.5 ml iodine diluted in 5ml distilled water

19.3.2.1. 1. If blue color appears, amylase or starch is present in the solution

19.3.2.2. 2. If reddish-brown color appears, glycogen is present

19.3.3. Important Note- Cellulose does not give this test.

19.3.3.1. Important Note- The color disappears on heating and reappears when the solution is cooled. If the color does not appear upon cooling, it indicates that iodine has vaporized during heating

19.4. 4. Seliwanoff’s Test

19.4.1. It is positive for monosaccharides with ketonic group. It is widely used to differentiate fructose, a keto sugar, from glucose and galactose

19.4.2. Seliwanoff’s reagent- 50 mg resorcinol + 33 ml of concentrated HCl in 100 ml of water

19.4.2.1. A cherry red color forms in the test tube upon cooling.

19.4.3. Important- Sucrose also gives a positive test because it is hydrolyzed to glucose and fructose. It is highly sensitive for sucrose even at 1% concentration

19.5. 5. Barfoed’s Test

19.5.1. It is a differentiating test to distinguish between monosaccharides and disaccharides.Monosaccharides give early positive test while the disaccharides give late positive.

19.5.2. Barfoed’s reagent- Copper Acetate in Glacial Acetic Acid

19.5.2.1. Formation of red precipitates after the initial first 5 minutes indicates the presence of a monosaccharide If precipitates are formed after 15 minutes, a disaccharide is present in the test solution

19.6. 6. Phloroglucinol test

19.6.1. This test is specifically to detect galactose and lactose in a solution.

19.6.2. Reagents- 10 ml concentrated HCl mixed with 8 ml of 0.5% phloroglucinol

19.6.2.1. When the solution is boiled and allowed to cool, it turns yellow to red indicates the presence of galactose/lactose in the solution.

19.7. 7. Bial Test

19.7.1. It is positive for pentose sugars (RNA, DNA)

19.7.2. Bial’s reagent is used that is made by dissolving 300 mg of orcinol in 100 ml of concentrated HCL and 0.25 mL ferric chloride solution.

19.7.2.1. A bluish color appears in the test tube upon heating indicates the presence of pentose sugar in the test solution

19.7.3. Hexoses form green color with Bial’s reagent.

19.8. 8. Tollens test

19.8.1. All monosaccharides and disaccharides except sucrose give positive tollens test.

19.9. 9. Fehling Test

19.9.1. All monosaccharides and disaccharides except sucrose give positive fehling test.

20. DPP/ Practice Material

20.1. https://drive.google.com/file/d/1h1HxMpjo2XHaZhlAi9S3nPSXXAZI9DO2/view?usp=sharing

20.2. https://drive.google.com/file/d/1R0ushP71t-MI961mp0IGL-7erKFCk8Ze/view?usp=sharing

20.3. https://drive.google.com/file/d/1YjSuGHWvQKIGmDPd-BTZ2UqHG3vbJbes/view?usp=sharing

20.4. https://drive.google.com/file/d/1jV7kuEPq3OTfEP_T75alZShkFOMoytvU/view?usp=sharing

20.5. https://drive.google.com/file/d/1Sov9k1svIY5HNDRTvejREouy5_0YFKP5/view?usp=sharing