أسترة فيشر لأسيتات الإيثيل

تخليق استر برائحة فاكهية

Organic Synthesis Advanced (University) 90 دقيقة ~$20,00

الهدف

تخليق أسيتات الإيثيل (رائحة مزيل طلاء الأظافر) عبر أسترة فيشر لحمض الأسيتيك والإيثانول بوجود حمض الكبريتيك كمحفز.

الخلفية

Fischer esterification is the acid-catalyzed condensation of a carboxylic acid with an alcohol to form an ester and water. The reaction is reversible, and excess alcohol is used to drive the equilibrium toward product formation. Ethyl acetate has a characteristic sweet, fruity smell and is widely used as an industrial solvent.

تحذيرات السلامة

  • Concentrated sulfuric acid is extremely corrosive
  • Glacial acetic acid causes burns
  • Ethanol and ethyl acetate are flammable — no open flames
  • Work in a fume hood
  • Add sulfuric acid slowly to the mixture

معدات الوقاية الشخصية المطلوبة

goggles gloves lab_coat

المواد

  • Glacial acetic acid (10 mL)
    Corrosive
  • Ethanol (absolute) (15 mL)
    Excess to drive equilibrium
  • Sulfuric acid (H₂SO₄) (2 mL)
    Concentrated, catalyst
  • Sodium bicarbonate solution (50 mL)
    5% for washing
  • Anhydrous sodium sulfate (5 g)
    Drying agent

المعدات

Round-bottom flask (100 mL) Reflux condenser Heating mantle Separating funnel Boiling chips Thermometer

الإجراء

1

Add 15 mL ethanol and 10 mL glacial acetic acid to the round-bottom flask with boiling chips.

3 دقيقة Handle acetic acid in fume hood
2

Slowly add 2 mL concentrated H₂SO₄ as catalyst. Swirl gently to mix.

3 دقيقة Add acid slowly — exothermic
3

Attach the reflux condenser and heat gently at reflux for 45 minutes.

45 دقيقة Ensure water is flowing through condenser
4

Cool the flask. Pour the contents into a separating funnel with 30 mL water.

5 دقيقة
5

Wash the organic layer with 25 mL of 5% NaHCO₃ to remove excess acid. Vent the funnel frequently.

5 دقيقة CO₂ gas released — vent carefully
6

Separate the organic layer (top) and dry over anhydrous Na₂SO₄ for 10 minutes.

12 دقيقة
7

Filter off the drying agent. Carefully smell the product by wafting — note the fruity aroma of ethyl acetate.

3 دقيقة Never sniff directly — waft vapors toward nose
8

Calculate the yield based on the volume collected and the theoretical yield.

5 دقيقة

النتائج المتوقعة

A clear, colorless liquid with a sweet, fruity smell characteristic of ethyl acetate. Typical yield is 60-70% due to the equilibrium nature of the reaction.

التنظيف

Dispose of organic waste in the designated container. Neutralize acid waste before disposal. Rinse all glassware with acetone then water.

Frequently Asked Questions

What is the objective of أسترة فيشر لأسيتات الإيثيل?
تخليق أسيتات الإيثيل (رائحة مزيل طلاء الأظافر) عبر أسترة فيشر لحمض الأسيتيك والإيثانول بوجود حمض الكبريتيك كمحفز.
How difficult is أسترة فيشر لأسيتات الإيثيل?
This experiment is rated as Advanced (University). It takes approximately 90 minutes to complete.
What safety precautions are needed for أسترة فيشر لأسيتات الإيثيل?
Key safety precautions include: Concentrated sulfuric acid is extremely corrosive; Glacial acetic acid causes burns; Ethanol and ethyl acetate are flammable — no open flames.
What materials are needed for أسترة فيشر لأسيتات الإيثيل?
The main materials required are: Glacial acetic acid, Ethanol (absolute), Sulfuric acid (H₂SO₄), Sodium bicarbonate solution, Anhydrous sodium sulfate.
What results should I expect from أسترة فيشر لأسيتات الإيثيل?
A clear, colorless liquid with a sweet, fruity smell characteristic of ethyl acetate. Typical yield is 60-70% due to the equilibrium nature of the reaction.