Lab: Preparation of Esters
Preparation of Esters
Introduction
Esters are known for their pleasant smells such as perfumes and artificial flavorings in contained labs. They are formed when a carboxylic acid reacts with alcohol and a strong acid such as a catalyst called sulfuric acid (H2SO4) for this lab. The structural formula for esters can be represented as R-COO-R’. The R and R’ symbolizes different alkyl groups that can be combined to the ester. When naming an ester the first part comes from the alcohol followed by the name of the carboxylic acid. Synthesizing for a complete reaction involves a strong acid which makes the esters a final product.
Purpose
The purpose of this lab is to complete four different synthesizing reactions and to identify its odors. Than followed by writing chemical equations for each reaction and ester formed.
Hypothesis
For test tube A I hypothesized that the final ester would be 2-methylpropyl formate. For test tube B I hypothesized the final ester would be octyl acetate. For test tube C I hypothesized it would be methyl salicylate. For test tube D I hypothesized it would be isopentyl acetate.
Materials and Methods
Apparatus
4 test tubes
Test tube rack
Graduated cylinder (10 mL)
150 mL beaker
250 mL beakers (2)
Hot plate
Thermometer
Safety glasses
Beaker tongs
Test tube holder
Reagents
Methanol
Methyl-2-propanol
1-pentanol
1-octanol
Acetic acid
Formic acid (methanoic acid)
Salicylic acid
Concentrated sulfuric acid (H2SO4)
Procedure
1. We labeled the four test tubes A to D and placed them in the test tube rack.
2. Into the appropriate test tubes, we poured the correct amount of an alcohol and added a carboxylic acid as indicated in the table below. We measured the salicylic acid on the balance. We also added four drops of concentrated sulfuric acid to each test tube.
Test tube
Alcohol
Carboxylic acid
A
1 mL methyl-2-propanol
1 mL formic acid
B
1 mL 1-octanol
1 mL acetic acid
C
1 mL
Introduction
Esters are known for their pleasant smells such as perfumes and artificial flavorings in contained labs. They are formed when a carboxylic acid reacts with alcohol and a strong acid such as a catalyst called sulfuric acid (H2SO4) for this lab. The structural formula for esters can be represented as R-COO-R’. The R and R’ symbolizes different alkyl groups that can be combined to the ester. When naming an ester the first part comes from the alcohol followed by the name of the carboxylic acid. Synthesizing for a complete reaction involves a strong acid which makes the esters a final product.
Purpose
The purpose of this lab is to complete four different synthesizing reactions and to identify its odors. Than followed by writing chemical equations for each reaction and ester formed.
Hypothesis
For test tube A I hypothesized that the final ester would be 2-methylpropyl formate. For test tube B I hypothesized the final ester would be octyl acetate. For test tube C I hypothesized it would be methyl salicylate. For test tube D I hypothesized it would be isopentyl acetate.
Materials and Methods
Apparatus
4 test tubes
Test tube rack
Graduated cylinder (10 mL)
150 mL beaker
250 mL beakers (2)
Hot plate
Thermometer
Safety glasses
Beaker tongs
Test tube holder
Reagents
Methanol
Methyl-2-propanol
1-pentanol
1-octanol
Acetic acid
Formic acid (methanoic acid)
Salicylic acid
Concentrated sulfuric acid (H2SO4)
Procedure
1. We labeled the four test tubes A to D and placed them in the test tube rack.
2. Into the appropriate test tubes, we poured the correct amount of an alcohol and added a carboxylic acid as indicated in the table below. We measured the salicylic acid on the balance. We also added four drops of concentrated sulfuric acid to each test tube.
Test tube
Alcohol
Carboxylic acid
A
1 mL methyl-2-propanol
1 mL formic acid
B
1 mL 1-octanol
1 mL acetic acid
C
1 mL