Transcript Presentation (Synthesis and Purification of Acetanilide)

Organic Chemistry I Lab
Acetylation of Aniline
and
Purification of Acetanilide
Follow the procedure given in the lab
manual for this experiment. Check
also various techniques utilized.
You will be given two vials for the
experiment:
**
**
The vial with the dark liquid contains 2 mL of
aniline
The vial with the transparent liquid contains
2.5 mL of acetic anhydride
Upon mixing the contents of the vials in a 125 mL
erlenmeyer flask with 15 mL of water, the product will form
after a little bit of swirling.
After the product is formed, add more water
and heat until the product dissolves
When the water solution ceases boiling,
***pour about 1 mL of the solution
into a clean beaker and keep it
***add charcoal to the solution
(carefully –frothing may occur)
***bring the solution to boiling again
and keep it boiling for a few
minutes
keep the charcoal solution hot
throughout the filtering process
Preparation of the collecting flask
 It
is necessary that the collecting flask and the
filter paper is kept hot to prevent the product
from recrystallizing on the filter paper.
Preparation of the collecting flask
 Add
10 mL of “hot” distilled water through the
fluted filter paper into the collecting flask
 Discard the water from the flask (once the
filter paper, the funnel and the flask are
warmed)
Filtering
Add the hot charcoal solution through the fluted
filter paper into the flask (a little at a time)
Notebook Write-up
•Give the title of the experiment
•Give the chemical reaction
•Give the names of the materials (under the reaction)
•Give the quantities of each of the starting materials used in the
reaction (both in mL and in mmol)
Remember this experiment is a synthesis, but it also utilizes a
“physical method” (charcoal treatment and recrystallization) to
purify the product.
You should decide yourselves what the most significant purpose
of the experiment is.
Notebook Write-up
You should have the following sections in your
notebook for this experiment:
Objectives:
Materials:
Hazards:
Procedure:
Results:
Discussion and Questions:
Notebook Write-up
Materials
There is no need for a separate entry, if you use
the chemical reaction for this purpose
Notebook Write-up
Hazards
You should look up all the possible hazards of the
materials you are using and also comment how
you intend to protect yourself against any of
these (for example, if any of the materials you are
using are skin irritants, you can overcome this
hazard considerably by wearing gloves)
List and discuss only the relevant hazards for you
in the lab
Notebook Write-up
Procedure
Do not copy the procedure from the lab manual.
Write a brief outline of the procedure. However,
make sure to indicate clearly if you deviate from
what is written in the lab manual
Notebook Write-up
Data
All the data in this experiment can be written in
the “Results” section.
Notebook Write-up
Results
This is the most important section (as always).
You have two types of results for this experiment:
1. Melting points of the
(i) unpurified and
(ii) charcoal purified product
2. Experimental yield (mass of your product).
However, you will not be able to measure either of these
physical properties until next week when your product is
totally dry.
Notebook Write-up
Discussion and Questions
Calculate the theoretical yield and the percentage yield
for the synthesis.
Comment on the purity of your product based on the
comparison of the melting points you measured with
literature melting points.
Answer the questions assigned.
HAVE FUN