Esters Lab
The reaction between a carboxylic acid and an alcohol produces an ester.
Safety: For this lab you must wear an apron/lab coat, gloves, and safety goggles at all times
Materials
3 test tubes
Thermometer
Hot plate
100 mL beaker
2 large beakers (250 mL)
Retort stand
Distilled water
Alcohol
Carboxylic acid
Sulfuric acid catalyst
Retort stand with clamp
Procedure
1. Prepare a hot-water bath: place about 125 mL of tap water in a 250 mL beaker on a hot plate. Use a
thermometer clamped to a retort stand in the bath to keep the bath between 50- 60℃ for the entire experiment.
2. Keep the thermometer from touching the beaker and monitor the temperature of the thermometer, not the
hotplate.
3. In the fume hood transfer 1.0 mL of your carboxylic acid into your labeled test tube.
4. In the same test tube transfer 1.0 mL of your alcohol.
5. Raise your hand so your teacher can put drops of H2SO4 in your test tube.
6. Cover your test tube with parafilm.
7. Leave the test tube in the hot water for 10 minutes. Use a thermometer to monitor the water temperature;
keep it between 50°C and 60°C
8. Prepare a cold-water bath: place about 125 mL of tap water with ice cubes in a 250 mL beaker.
9. Place the test tube in the cold water bath for 5 minutes.
10. Transfer your mixture into an empty 100 mL beaker. Add a few drops of distilled water. Waft the odour. Record
the odour.
Observation table
Test Tube
Carboxylic Acid
Alcohol
A
B
C
Time in Hot Bath
A
B
C
Time in Cold Bath
Resulting Smell
Ester Preparation PreLab
Name: ____________________
1. Write a purpose for this lab: _______________________________________________________________
_______________________________________________________________________________________
2. Why is it important to waft the odor produced instead of putting your face directly over the beaker?
3. Complete the following Esterification reactions including all names, drawings and catalysts.
ethanoic acid + pentan-1-ol
ethanoic acid + propan-1-ol
ethanoic acid + butan-1-ol
benzoic acid + methanol
2-hydroxybenzoic acid (Salicylic acid) + methanol
4. Use the chart to predict the odour produced by each product formed in question three. Include the smell
in the table.
ALCOHOL
Sec-butyl alcohol: butan-2-ol
N-butyl alcohol: butanol
N-propyl alcohol: propanol
Methanol
CARBOXYLIC ACID
Methanoic Acid
Ethanoic Acid
Benzoic Acid
Salicylic Acid
0
