Extraction Lab

What is the first step in the extraction procedure?

Work in groups of two, with each person performing the extraction.

How much NaOH solution should be placed in the Erlenmeyer flask?

~20 mL

What is the purpose of placing the NaOH solution on ice?

To keep the solution cold during the extraction process.

What is the weight of the unknown compound to be dissolved in ethyl acetate?

0.25 g

What should you do after adding the ethyl acetate solution to the separatory funnel?

Add 10 mL of HCl solution.

What is the purpose of venting the separatory funnel?

To release any gas that may have built up during shaking.

What is collected as the acidic extract?

The aqueous (bottom) layer drained into a clean Erlenmeyer flask.

What should be done to the acidic extract to isolate the unknown base?

Neutralize it with cold NaOH solution while in an ice bath.

What indicates that the unknown base has precipitated out of solution?

The appearance of precipitate after neutralization.

What is the next step after filtering the solution with a Buchner funnel?

Scrape the solids onto a labeled weigh boat.

What is the first step in isolating the unknown neutral compound?

Drain the remaining ethyl acetate solution into a small Erlenmeyer flask.

What should be added to the ethyl acetate solution to remove water?

Approximately 4 spatulas worth of sodium sulfate.

What equipment is used for simple distillation in 220C?

A 50 mL round bottom flask and a 100 mL round bottom flask.

What is the melting point range for 4-nitroaniline?

149-151 °C

What is the melting point range for anthracene?

216-218 °C

What is the melting point range for 9-fluorenone?

82-85 °C

What is the melting point range for phenanthrene?

101-103 °C

Extraction

In the extraction step, components of a mixture are partitioned between immiscible solvents based on their solubility and acid-base properties.

General Rules

You cannot start over if no solid is collected; stockroom will not provide a new sample.

Troubleshooting

If base does not precipitate, blow air over the solution to evaporate ethyl acetate and force precipitation.

Separatory Funnel Notes

Always remove glass stopper before draining to prevent vacuum lock.

Safety Analysis

Key Hazards include Ethyl Acetate, Sodium Hydroxide, Hydrochloric Acid, Sodium Sulfate, Nitroanilines, Fluorenone, Anthracene, Phenanthrene, and Methanol.

Ethyl Acetate

Flammable, causes dizziness, skin/eye irritation. Avoid flames; use in fume hood.

Sodium Hydroxide (NaOH)

Strong base, corrosive to skin/eyes, causes burns. Wear gloves/goggles.

Hydrochloric Acid (HCl)

Corrosive, causes burns and inhalation hazards. Handle in hood, use PPE.

Sodium Sulfate

Drying agent, mild irritant. Avoid inhalation/skin contact.

Nitroanilines

Toxic, harmful by skin absorption or inhalation. Use gloves, goggles, hood.

Fluorenone, Anthracene, Phenanthrene

Irritants, some are possible carcinogens. Handle with care.

Methanol

Highly flammable, toxic, can cause blindness if ingested. Avoid inhalation, skin contact, flames.

Emergency Response - Skin/eye contact

Flush with water for 15+ minutes, seek medical help.

Emergency Response - Inhalation

Move to fresh air, seek medical help.

Emergency Response - Ingestion

Do not induce vomiting; rinse mouth, seek immediate medical attention.

Ethyl Acetate CAS No.

141-78-6

Ethyl Acetate Physical State

liquid

Ethyl Acetate Color

colorless

Ethyl Acetate Odor

fruity

Ethyl Acetate Flash Point (FP)

-3 °C

Ethyl Acetate Boiling Point (BP)

76.5-77.5 °C

Ethyl Acetate Melting Point (MP)

-84 °C

Ethyl Acetate Density (d)

0.902 g/mL

Ethyl Acetate Vapor Pressure (VP)

73 torr @ 20 °C

Ethyl Acetate Solubility (Sol)

soluble in water

Carcinogenicity

Not a known carcinogen.

Mutagenicity

Possible mutagen.

Sodium Hydroxide

Solid, white, odorless substance with a melting point (MP) of 318 °C and a boiling point (BP) of 1390 °C.

CAS No.

Chemical Abstracts Service Registry Number.

PS

Physical state of the substance.

Color

Describes the appearance of the substance.

Odor

Describes the smell of the substance.

FP

Flash point, the temperature at which the substance can ignite.

BP

Boiling point, the temperature at which the substance transitions from liquid to gas.

MP

Melting point, the temperature at which the substance transitions from solid to liquid.

d

Density or specific gravity of the substance, measured in g/mL.

VP

Vapor pressure at specified temperature (°C).

VD

Vapor density relative to air (1.0).

Sol

Solubility in water.

Acute Hazards/Symptoms

Immediate health effects resulting from exposure.

Inhalation Symptoms

Irritation, sore throat, burning sensation, laryngitis, coughing, destruction of mucous membranes, headache, nausea, vomiting, and delayed pulmonary edema.

Skin Symptoms

Redness, cutaneous burns, and skin fissures.

Eye Symptoms

Disintegration and sloughing of conjunctival and corneal epithelium, corneal opacification, edema, ulceration, and blindness.

Ingestion Symptoms

Corrosion of the lips, mouth, tongue, pharynx, severe esophageal and abdominal pain, and vomiting.

Hydrochloric Acid Solutions

Liquid, colorless or yellow substance with a density of 1.07-1.18 g/mL and a boiling point of 110 °C.

Acute Hazards/Symptoms (Hydrochloric Acid)

Burning of the throat, coughing, choking, inflammation, ulceration of the nose, throat or larynx, bronchitis, pneumonia, palpitations, and headache.

Skin Symptoms (Hydrochloric Acid)

Severe irritation, inflammation, ulceration, necrosis, chemical burns, shock, rapid pulse, sweating, and collapse.

Eye Symptoms (Hydrochloric Acid)

Severe irritation, conjunctivitis, corneal necrosis, and burns with impairment or permanent loss of vision.

Ingestion Symptoms (Hydrochloric Acid)

Burns of the mouth, throat, esophagus and stomach, pain, uneasiness, nausea, salivation, vomiting, diarrhea, chills, shock and intense thirst.

Fire Hazard

Negligible fire hazard for both Sodium Hydroxide and Hydrochloric Acid.

3-Nitroaniline

CAS No. 99-09-2; solid, yellow; d = 1.43 g/mL; Sol = 0.089 g/L.

4-Nitroaniline

CAS No. 100-01-6; solid, pale yellow; d = 1.424 g/mL; Sol = slightly soluble.

Flash Point (FP)

The temperature at which a substance can vaporize to form an ignitable mixture in air.

Boiling Point (BP)

The temperature at which a liquid's vapor pressure equals the external pressure surrounding the liquid.

Melting Point (MP)

The temperature at which a solid becomes a liquid.

Density (d)

Mass per unit volume of a substance, expressed in g/mL.

Vapor Pressure (VP)

The pressure of a vapor in thermodynamic equilibrium with its condensed phases at a given temperature.

Vapor Density (VD)

The density of a vapor relative to air (1.0).

Solubility (Sol)

The ability of a substance to dissolve in a solvent, typically water.

Inhalation Hazard

Can cause irritation or harmful effects; specific symptoms include cyanosis and delayed onset.

Skin Contact Hazard

Can cause irritation or be fatal if absorbed through skin; requires protective gloves and clothing.

Eye Contact Hazard

Can cause irritation; requires safety goggles and immediate flushing with water.

Ingestion Hazard

Can cause diarrhea, fluid loss, and hypotension; requires immediate medical attention.

First Aid for Inhalation

Remove to fresh air; if breathing is difficult, give oxygen and seek medical advice.

First Aid for Skin Contact

Immediately flush skin with soap and copious amounts of water for at least 15 minutes.

First Aid for Eye Contact

Immediately flush eyes with copious amounts of water and seek medical advice.

First Aid for Ingestion

Wash out mouth with water and call a physician; if vomiting occurs, keep head lower than hips.

Material Safety Data Sheet (MSDS)

A document that provides detailed information about a substance's hazards and safety precautions.

Remove contaminated clothing.

Action to take when clothing is contaminated.

Irritating to the eyes.

Description of the effect on eyes.

Safety goggles.

Recommended protective eyewear.

Immediately flush eyes with copious amounts of water lifting upper and lower lids often.

First aid procedure for eye exposure.

Seek medical advice.

Action to take after flushing eyes.

Toxic if swallowed.

Danger associated with ingestion.

Exposure to and/or consumption of alcohol may increase toxic effects.

Warning regarding alcohol interaction.

Exposure can cause headache, unconsciousness, coughing, chest pains, difficulty breathing, nausea, cyanosis, ataxia, diarrhea, and vomiting.

Symptoms of exposure.

Not a known carcinogen.

Carcinogenicity status of the compound.

Not a known mutagen.

Mutagenicity status of the compound.

Consult the Material Safety Data Sheet for this compound.

Recommendation for detailed information.

PS.

Physical state of the compound.

FP.

Flash point (°C).

BP.

Boiling point (°C) @ 760 torr unless otherwise stated.

MP.

Melting point (°C).