"Synthesis of Paracetamol by using p-amino phenol"

 

"Synthesis of Paracetamol by using p-amino phenol"

Theory:

Paracetamol, also known as acetaminophen, is a widely used analgesic and antipyretic drug. Its chemical name is N-acetyl-para-aminophenol. Paracetamol can be synthesized through a multi-step reaction starting from phenol.

Chemicals Required:

• 4-Aminophenol
• Acetic anhydride
• Concentrated sulfuric acid
• Distilled water

Apparatus Required:

1. Round-bottom flask
2. Reflux condenser
3. Separatory funnel
4. Filtration setup
5. Vacuum pump
6. Glass stirring rod
7. Beakers
8. Heating mantle
9. pH meter
10. Thermometer

Chemical Equation:

Mechanism:

Procedure:

Acetylation:

a. In a round-bottom flask, combine 20 g of 4-aminophenol with 50 mL of acetic anhydride.

b. Add a few drops of concentrated sulfuric acid to the flask.

c. Reflux the mixture for 3-4 hours at a temperature of 120-130°C.

d. Stir the reaction mixture intermittently during refluxing.

Cooling and Filtration:

a. Allow the reaction mixture to cool to room temperature.

b. Pour the mixture into a beaker containing cold water.

c. Filter the precipitated paracetamol using a Buchner funnel and wash it with water.

Drying and Purification:

a. Dry the paracetamol precipitate by suction filtration using a vacuum pump.

b. Purify the dried paracetamol by recrystallization from a suitable solvent (e.g., ethanol).

Calculations

Calculate the molar mass of 4-aminophenol

Molar mass of 4-aminophenol (C₆H₇NO) = (12.01 g/mol × 6) + (1.01 g/mol × 7) + (14.01 g/mol) + (16.00 g/mol)

Molar mass of 4-aminophenol = 109.13 g/mol

Moles of 4-aminophenol = Mass of 4-aminophenol / Molar mass of 4-aminophenol

Moles of 4-aminophenol = 20 g / 109.13 g/mol ≈ 0.183 mol

Since the acetylation reaction involves a 1:1 stoichiometry between 4-aminophenol and paracetamol, the moles of paracetamol formed will also be 0.183 mol.

Yield Calculation:

Assuming an ideal situation with a 100% yield, the yield of paracetamol would be 0.183 mol.

To calculate the mass of paracetamol

Mass of paracetamol = Moles of paracetamol × Molar mass of paracetamol = 0.183 mol × (12.01 g/mol × 8 + 1.01 g/mol × 9 + 14.01 g/mol + 16.00 g/mol × 2) ≈ 19.36 g

Mass of paracetamol = 19.36 g

Precautions:

• Wear appropriate personal protective equipment (lab coat, gloves, safety goggles) while handling chemicals.
• Perform the synthesis in a well-ventilated fume hood to avoid inhalation of toxic fumes.
• Use caution while handling concentrated sulfuric acid and acetic anhydride, as they are corrosive.
• Follow good laboratory practices and adhere to local safety regulations.
• Dispose of chemical waste properly according to safety guidelines.

"Extraction of Piperine from Black Pepper"

 

Extraction of Piperine from Black Pepper

Introduction:

This experiment aims to extract piperine, the active compound responsible for the pungent taste and health benefits in black pepper. Piperine is a bioactive alkaloid with various medicinal properties, making it a valuable compound to isolate and study. The extraction process involves the use of a suitable organic solvent to isolate piperine from the crushed black pepper.

Theory:

Piperine (C₁₇H₁₉NO₃) is a crystalline alkaloid found in black pepper. It is responsible for the pepper's characteristic pungency and acts as a bioenhancer, enhancing the absorption of various nutrients and drugs. In this experiment, the piperine will be extracted from black pepper using an organic solvent through a process called solvent extraction.

Chemicals:

• Black Pepper (ground)
• Ethanol (95% or higher purity)
• Distilled Water

Glassware:

• Conical Flask
• Separatory Funnel
• Glass Stir Rod
• Buchner Funnel
• Filter Paper

Procedure:

1. Weigh 50g of ground black pepper and transfer it to a conical flask.
2. Add 200 mL of ethanol to the flask and stir the mixture using a glass rod.
3. Let the mixture sit for about 30 minutes, stirring occasionally to enhance extraction.
4. Set up a Buchner funnel with filter paper and filter the mixture to separate the solid residue (undissolved particles) from the ethanol extract.
5. Transfer the filtrate (ethanol extract) to a separatory funnel.
6. Add 50 mL of distilled water to the separatory funnel and shake gently to allow for phase separation.
7. Allow the two layers to settle, with the denser water layer at the bottom and the lighter ethanol layer at the top.
8. Carefully drain the bottom water layer, leaving behind the ethanol extract (containing piperine) in the separatory funnel.
9. Transfer the ethanol extract to a pre-weighed evaporating dish.
10. Evaporate the ethanol using a water bath or a rotary evaporator to obtain the crude piperine.

Calculations:

Given data: Initial amount of black pepper = 50 grams 

Concentration of piperine in the extracted crude extract= 5%

Step 1:

Calculate the amount of piperine in the extracted crude extract.

Amount of piperine = Volume of crude extract X Concentration of piperine

Assuming the volume of crude extract is 100 mL;

Amount of piperine = 100 mL X 5% (0.05) 

Amount of piperine = 5 grams

Step 2:

Calculate the percentage yield.

Percentage yield = (Amount of Crude Piperine Obtained / Initial Mass of Black Pepper) X 100

Percentage yield = (5 g / 50 g) X 100

Percentage yield = 10%

Therefore, based on the given data, the percentage yield of piperine from the extraction of 50 grams of black pepper would be 10%.

Observations:

Piperine (C₁₇H₁₉NO₃)

Color of Piperine: Piperine is a yellowish-brown crystalline compound.

Molar Mass: 285.34 g/mol

Melting Point: The melting point of piperine is approximately 128-131°C.

Precautions:

• Work in a well-ventilated area to avoid inhalation of ethanol vapors.
• Wear appropriate personal protective equipment, including lab coats and gloves.
• Use a fume hood when handling volatile solvents.
• Handle the glassware with care to avoid breakage and injury.
• Avoid direct contact with eyes, skin, and mouth when handling black pepper or piperine.

Conclusion:

This experiment successfully demonstrates the extraction of piperine from black pepper using ethanol as the solvent. The obtained crude piperine can further be purified and analyzed for its potential medicinal properties.

"Extraction of Limonene from Orange Peel Using a Soxhlet Apparatus"

 

Extraction of Limonene from Orange Peel Using a Soxhlet Apparatus

Theory:

The extraction of limonene from orange peel is a common procedure used to isolate this valuable compound for various industrial and research applications. Limonene is a cyclic terpene hydrocarbon found abundantly in the essential oils of citrus fruits, particularly in orange peel. The Soxhlet extraction method is employed to separate limonene from the peel using a non-polar solvent, typically hexane or petroleum ether. The Soxhlet apparatus allows for efficient extraction by repeatedly boiling the solvent, which vaporizes and then condenses, cycling through the solid material multiple times. This continuous process maximizes the extraction efficiency, ensuring a higher yield of limonene.

Chemicals Required:

• Orange peels (dried and finely ground) - 50 g
• Hexane or petroleum ether (solvent) - 500 mL

Apparatus Required:

• Soxhlet apparatus (consisting of a round-bottom flask, Soxhlet extractor, condenser, and a collection flask)
• Heating mantle 
• Separatory funnel
• Glass wool 
• Weighing balance
• Glassware
• Vacuum filtration setup

Procedure:

1. Set up the Soxhlet apparatus by attaching the condenser, Soxhlet extractor, and round-bottom flask. Place a glass wool plug or filter paper in the extractor to prevent the solid material from entering the condenser.
2. Weigh approximately 50 g of dried and finely ground orange peels.
3. Add the orange peels into the Soxhlet extractor.
4. Fill the round-bottom flask with 500 mL of hexane or petroleum ether.
5. Assemble the Soxhlet apparatus and connect the condenser to a water source for cooling.
6. Set up a heating mantle or hot plate/stirrer beneath the round-bottom flask and switch it on.
7. Begin heating the flask gradually, allowing the solvent to boil and vaporize. As the solvent vapor rises, it condenses in the condenser and drips back into the Soxhlet extractor, cycling through the orange peels.
8. Continue the extraction process for 6-8 hours to ensure a thorough extraction of limonene.
9. After the extraction, disconnect the Soxhlet apparatus and remove the round-bottom flask containing the extracted solution.
10. Transfer the extracted solution into a separatory funnel and allow the two phases to separate.
11. Drain the lower aqueous layer and collect the upper organic layer (containing limonene) in a clean beaker.
12. Perform a vacuum filtration to remove the solvent and concentrate the limonene.
13. Calculate the yield of limonene by measuring the weight or volume of the collected limonene.
14. Store the extracted limonene in a properly labeled and tightly sealed container for future use.

Observation:

Boiling Point: 176-177°C (349-351°F) at atmospheric pressure.

Melting Point: -74°C (-101°F).

Color: Limonene is a colorless liquid.

Molar Mass: 136.24 g/mol.

Molecular Structure: Limonene has a molecular formula of C₁₀H₁₆, indicating it consists of 10 carbon atoms and 16 hydrogen atoms. It is a cyclic terpene and belongs to the class of monocyclic monoterpenes.

Calculations:

Let's assume the weight of the extracted limonene is 2.5 grams, and the weight of the orange peels used is 50 grams. We can now calculate the yield of limonene.

Yield of Limonene (%) = (Weight of extracted limonene / Weight of orange peels) x 100

Yield of Limonene (%) = (2.5 g / 50 g) x 100

Yield of Limonene (%) = 0.05 x 100

Yield of Limonene (%) = 5%

Therefore, the yield of limonene from the extraction process is 5%.

Precautions:

• Work in a well-ventilated area or under a fume hood due to the use of organic solvents.
• Handle the Soxhlet apparatus and hot glassware with caution to avoid burns.
• Ensure the apparatus is properly assembled and securely clamped to prevent accidents.
• Use heat-resistant gloves and eye protection during the experiment.
• Avoid inhaling vapors of the solvent. Keep away from open flames and sources of ignition.
• Dispose of waste materials and organic solvents properly according to local regulations.

"Extraction of caffeine from Coffee beans"

 

Extraction of caffeine from Coffee beans

Theory:

Caffeine is a natural alkaloid found in coffee, and it is soluble in both water and organic solvents. The extraction of caffeine from coffee beans involves the use of solvents to separate the caffeine from the coffee grounds.

Materials:

• Coffee beans (100 grams)
• Distilled water (approximately 1 liter)
• dichloromethane (100 mL)
• Sodium carbonate (Na2CO3) (10 grams)
• Hydrochloric acid (HCl) (10 mL)
• Anhydrous sodium sulfate (Na₂SO₄) (a few grams)

Glassware

• Flask
• Funnel
• Filter paper
• Evaporating dish
• Hot plate
• Glass rod
• Mortar and pestle

Procedure:

1. Grind 100 grams of coffee beans using a mortar and pestle to increase the surface area for extraction.
2. Transfer the ground coffee to a beaker and add approximately 1 liter of distilled water to create a slurry.
3. Add 10 grams of sodium carbonate to the beaker and stir the mixture well to dissolve the sodium carbonate. This creates an alkaline environment for extraction.
4. Heat the beaker gently on a hot plate or Bunsen burner for about 15 minutes while stirring with a glass rod. This step is called extraction.
5. After extraction, filter the mixture using a funnel and filter paper to separate the liquid (filtrate) from the solid coffee grounds. Collect the filtrate in another beaker.
6. Transfer the filtrate to a separating funnel and add 100 mL of the organic solvent (e.g., dichloromethane or ethyl acetate).
7. Carefully shake the separating funnel to allow the solvent and water to separate into two layers. After separation, remove the lower aqueous layer and discard it.
8. Transfer the organic solvent layer (containing caffeine) to an evaporating dish.
9. Add a small amount (a few grams) of anhydrous sodium sulfate to the evaporating dish to remove any remaining water.
10. Evaporate the organic solvent using gentle heat to obtain a residue, which will contain caffeine.
11. Weigh the evaporating dish with the residue to determine the mass of caffeine extracted.
12. Perform calculations to determine the percentage of caffeine extracted by dividing the mass of caffeine obtained by 100 grams (initial mass of coffee beans) and multiplying by 100.

Calculations:

Step 1:

Calculate the amount of caffeine in the extracted residue;

Amount of caffeine = Mass of extracted residue * Concentration of caffeine

Amount of caffeine = X grams * 1% (0.01)

Amount of caffeine = 0.01X grams

Step 2:

Calculate the percentage yield;

Percentage yield = (Amount of caffeine / Initial amount of coffee beans) * 100

Percentage yield = (0.01X grams / 100 grams) * 100

Percentage yield = 0.01X

Let's assume that after the extraction and evaporation steps, you obtained a residue with a mass of 0.5 grams.

Substituting this value into the equation:

Percentage yield = 0.01 * 0.5

Percentage yield = 0.005 * 100

Percentage yield = 0.5%

Therefore, the percentage yield of caffeine extraction from coffee beans would be approximately 0.5%.

Observations:

Molecular Structure:

Molecular Formula: C₈H₁₀N₄O₂

Molar Mass: 194.22 g/mol

Color: Caffeine is a white crystalline soild.

Melting Point: Caffeine has a melting point of 238-240°C

Boiling Point: Caffeine has a boiling point of 178°C at normal atmospheric pressure.

Precautions:

• Follow proper safety protocols when working with chemicals such as sodium carbonate, hydrochloric acid, and organic solvents.
• Use appropriate personal protective equipment, such as gloves and safety glasses.
• Ensure that the experiment is conducted in a well-ventilated area or under a fume hood to avoid inhalation of harmful fumes or vapors.
• Be cautious when working with heating sources and flammable solvents.
• Handle glassware carefully to avoid breakage or injury. Inspect glassware for cracks or damage before use.
• Dispose of chemicals, solvents, and waste materials according to local regulations and guidelines.

"Extraction of Nicotine from Tobacco Leaves"

 

"Extraction of Nicotine from Tobacco Leaves"

Theory:

Nicotine is an alkaloid primarily found in tobacco (Solanaceae Family), as well as in smaller quantities in tomato plants and green peppers. It is also present in the Coca plant. Nicotine was first isolated from tobacco plants in 1828 by German chemists Posselt and Reimann. It is a potent neurotoxin and is used in various insecticides.

Apparatus Required:

• 250 ml beaker
• Separatory funnel
• Measuring cylinder
• Hot plate
• Magnetic stirrer
• Weighing balance
• Iron stand
• Pipette

Chemicals Required:

• 5% NaOH solution
• Diethyl ether
• Tobacco leaves
• Distilled water

Structure:

Procedure:

1. Clean and dry all the apparatus carefully.
2. Take 10g of tobacco leaves, wash them thoroughly, and ensure they are completely dried.
3. Grind the leaves and add them to a solution of 100g 5% NaOH.
4. Stir the mixture thoroughly and filter the solution.
5. Dilute the filtrate with 30ml of distilled water to remove impurities.
6. Heat the solution on a hot plate until it boils and a strong smell of nicotine is obtained.
7. Transfer the solution into a separatory funnel and extract it by adding 25ml of diethyl ether. Repeat the extraction process three times.
8. Evaporate the ether using a hot plate placed in an ice bath.
9. Separate the upper brown layer of nicotine oil.

Result: The yield of nicotine oil obtained was 3.8 ml.

Calculations:

Initial amount of tobacco leaves = 10 grams

Concentration of nicotine in the extracted oil = 5%

Step 1:

Calculate the amount of nicotine in the extracted oil: Amount of nicotine = Volume of nicotine oil * Concentration of nicotine Amount of nicotine = 3.8 ml * 5% (0.05) Amount of nicotine = 0.19 grams

Step 2:

Calculate the percentage yield:

Percentage yield = (Amount of nicotine / Initial amount of tobacco leaves) * 100

Percentage yield = (0.19 g / 10 g) * 100

Percentage yield = 1.9%

Therefore, with the new assumptions, the percentage yield of nicotine oil would also be approximately 1.9%.

Observations:

Molecular Formula: C₁₀H₁₄N₂

Molar Mass: 162.23 g/mol

Color: Nicotine is a colorless to pale yellow liquid in its pure form.

Melting Point: Nicotine has a melting point of -79°C (-110°F).

Boiling Point: Nicotine has a boiling point of 247°C (477°F) at normal atmospheric pressure.

Precautions:

• Always wear gloves while conducting the experiment.
• Use a mask to protect against the pungent smell of nicotine oil.  
• Ensure thorough cleaning and drying of apparatus before use.
• Handle nicotine with caution due to its neurotoxic properties.
• Follow proper disposal protocols for chemical waste generated during the experiment.

“Lab Report For The Synthesis of Chalcone”

 

“Lab Report For The Synthesis of Chalcone”

Theory:

Chalcone is synthesized through the Claisen-Schmidt condensation reaction between an aromatic aldehyde and an acetophenone or ketone. The reaction is catalyzed by a base, usually a strong base like sodium hydroxide, and proceeds through the formation of an enolate intermediate. The enolate reacts with the aldehyde to form the chalcone product.

Chemicals Used:

1. Sodium hydroxide (NaOH) - 5.5 grams
2. Water - 50 ml
3. Rectified spirit - 30 ml
4. Ice - 13 grams
5. Acetophenone - 14 ml
6. Benzaldehyde - 11 ml

Apparatus Used:

• Magnetic stirrer
• Glass beaker 
• Stir bar
• Weighing scale
• Filtration setup
• Drying apparatus

Chemical Equation:

Mechanism:

Procedure:

1. Dissolve 5.5 grams of sodium hydroxide (NaOH) in 50 ml of water to prepare a sodium hydroxide solution.
2. Add 30 ml of rectified spirit (ethanol) to the sodium hydroxide solution.
3. Add 13 grams of ice to the solution and stir until it is dissolved.
4. Add 14 ml of acetophenone to the mixture and shake well.
5. Add 11 ml of benzaldehyde to the solution and observe the formation of a milky white mixture.
6. Maintain the temperature below 20°C, preferably by placing the reaction vessel in an ice bath or a cold-water bath.
7. Place the reaction vessel on a magnetic stirrer and stir the solution for 2 hours with the vessel covered.
8. After 2 hours, the solution should become thick and change color from white to yellow.
9. The yellow precipitate formed is chalcone.
10. Filter the chalcone precipitate using a filtration setup (e.g., Buchner funnel) to separate it from the liquid portion.
11. Wash the chalcone precipitate with a small amount of cold solvent (e.g., rectified spirit) to remove impurities.
12. Dry the chalcone product using a suitable drying apparatus (e.g., desiccator) to remove any residual solvent.