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Experimental procedure

CAUTION WEAR EYE PROTECTION!

 

CAUTION - Concentrated sulfuric acid will burn and stain the skin as well as damage clothing. In case of skin or clothing contact, wash the area immediately with large amounts of water.

Synthesis of esters

  • Place approximately 2 g (or 2 mL if the substance is a liquid) of the organic acid and 2 mL of the alcohol in a large test tube.
  • Add 5 - 7 drops of concentrated (18 M) sulfuric acid, mix the solution well with a glass stirring rod and then place the test tube in a hot water bath (largest beaker in your drawer) (~ 80°C) for 5 - 10 minutes.
  • Remove the test tube from the hot water bath and cautiously pour the mixture into about 15 mL of saturated sodium bicarbonate contained in a small beaker. The sodium bicarbonate will destroy any unreacted acid.
  • Observe the aroma produced from each of the following esterification reactions. Write the structure of the esters produced, and the balanced equations for the esterification and the acid/sodium bicarbonate reactions:

 

Complete the following reactions using the procedure above and record your observations.

 

 (1) C 7 H 6 O 3 + CH 3 OH size 12{C rSub { size 8{7} } H rSub { size 8{6} } O rSub { size 8{3} } + ital "CH" rSub { size 8{3} } ital "OH" rightarrow } {}

 salicylic acid + methyl alcohol

 (2) CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 OH + CH 3 COOH size 12{ ital "CH" rSub { size 8{3} } ital "CH" rSub { size 8{2} } ital "CH""" lSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "OH"+ ital "CH" rSub { size 8{3} } ital "COOH" rightarrow } {}

1 - octanol + glacial acetic acid

 (3) CH 3 CH 2 CH 2 CH 2 CH 2 OH + CH 3 COOH size 12{ ital "CH" rSub { size 8{3} } ital "CH" rSub { size 8{2} } ital "CH""" lSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "OH"+ ital "CH" rSub { size 8{3} } ital "COOH" rightarrow } {}

 amyl alcohol + glacial acetic acid

(4) C 2 H 5 OH + CH 3 COOH size 12{C rSub { size 8{2} } H"" lSub { size 8{5} } ital "OH"+ ital "CH" rSub { size 8{3} } ital "COOH" rightarrow } {}

ethanol + acetic acid

 

Oxidation of an alcohol with acidified potassium dichromate(vi) solution

  • Add 10 drops of dilute sulfuric acid (6M) and 5 drops of potassium dichromate(VI) solution (0.01M) to 5 drops of ethanol. The oxidising agent is added slowly to the alcohol so that the temperature is kept below that of the alcohol and above that of the carbonyl compound. (Carbonyl compounds are more volatile than the corresponding alcohols). Usually the alcohol is in excess of the oxidant and the aldehyde is distilled off to avoid further oxidation.
  • Note the color and smell cautiously (Royal Wave).
  • Warm the mixture and smell cautiously (Royal Wave).
  • Repeat the experiment using first methanol and then propan-2-ol in place of ethanol.

 

Describe what happens and explain the color changes.

What conditions and techniques would favour the oxidation of ethanol to

a. ethanal rather than ethanoic acid.

b. ethanoic acid rather than ethanal?

Oxidation of an alcohol with acidified potassium permanganate (vii) solution

  • Add 10 drops of dilute sulfuric acid and 5 drops of potassium permanganate (VII) solution (0.01M) to 5 drops of ethanol. Note the color and smell cautiously.
  • Warm the mixture and smell cautiously (Royal Wave).
  • Repeat the experiment using first methanol and then propan-2-ol in place of ethanol.
  • Take the pH of your final mixture using Universal indicator paper

 Describe what happens and explain the color changes.

What is your final product?

Saponification of a vegetable oil

CAUTION - Sodium hydroxide is a very caustic material that can cause severe skin burns. Eye burns caused by sodium hydroxide are progressive: what at first appears to be a minor irritation can develop into a severe injury unless the chemical is completely flushed from the eye. If sodium hydroxide comes in contact with the eye, flush the eye with running water continuously for at least 20 minutes. Notify your TA immediately. If sodium hydroxide is spilled on some other parts of the body, flush the affected area with running water continuously for at least 2-3 minutes. Notify your TA immediately.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Honors chemistry lab fall. OpenStax CNX. Nov 15, 2007 Download for free at http://cnx.org/content/col10456/1.16
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