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Some Important Definitions:

Chiral: An object that is not superimposable on its mirror image.

Isomers: Different molecules with the same molecular formula.

Constitutional isomers: Isomers that differ in the connectivities of atoms.

Stereoisomers: Isomers that are not constitutional isomers. These differ in the spatial arrangement of atoms.

Enantiomers: Stereoisomers that are non-superimposable mirror images.

Diastereomers: Stereoisomers that are not enantiomers. (Compounds with more than one stereocenter)

Fig 2.1: Summary of isomerism

Meso Compounds: A compound that contains exactly one stereocenter is always chiral. However, compounds that contain more than one stereocenter are not necessarily chiral. This occurs when multiple stereocenters create an internal plane of symmetry. For example, consider 2,3-dichlorobutane. There are four possible stereochemical permutations since there are two stereocenters:

Figure 4: Stereoisomers of 2,3-dichlorobutane

Figure 4.2: Four possible stereoisomers of 2-bromo-3-chlorobutane

Prelab: extraction of carvone

(Total 10 Points)

On my honor, in preparing this report, I know that I am free to use references and consult with others. However, I cannot copy from other students’work or misrepresent my own data.

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1. Assign the configurations of the two stereocenters in the compound below. (2 points)

2. Assign R or S configuration to the following molecules. (3 points)

3. Between the stress of university and your diet consisting entirely of pizza, potato chips, and chocolate bars, you have developed an ulcer. In order to numb the burning in your stomach, you take Pepcid. The active ingredient in Pepcid, famotidine, has the structure shown below. For the atoms indicated, identify the hybridization (5 points)

Grading

  • Completion of Pre-Lab Questions.
  • Write-up in your Lab Notebook).
  • Completion of Report Questions.
  • TA Points.

Materials required

Equipment Chemicals
30 mL beaker Caraway seeds
Hirsch funnel Ether
Filter paper Spearmint leaves
TLC plates 10% ethyl acetate in hexane
Blotter p-anisaldehyde stain
Tubes

Safety

Wear gloves all the time. Keep safety glasses on all the time to avoid unwanted accidents. Dispose organic substances in the proper container.

Experimental procedure

1) Measure 2 g of crushed caraway seeds into a 30 mL beaker and add 10 mL of ether. Ether is chosen as a solvent because the carvone is soluble in ether. Cover with aluminum foil to prevent evaporation and allow the mixture to stand for 15-30 minutes.

2) Measure 2 g of spearmint leaves into a 50 mL beaker and add 10 mL of ether. Again, cover with aluminum foil and allow the mixture to stand for 15-30 minutes. The different containers have no effect on the extraction; they simply allow you to do two extractions simultaneously without duplicating your glassware.

3) Once the seeds have soaked for the appropriate time, use a Hirsch funnel to filter the caraway seed solution (Always clamp a filter flask.). This is done by placing a piece of filter paper in the funnel, assembling the Hirsch funnel as shown in the diagram below, and starting the suction such that a vacuum builds up in the filter flask. Pre-wet the filter paper with ether, then pipette the liquid from the extraction into the funnel and collect the liquid in the receiving flask. When you have filtered the caraway seed solution, transfer the filtrate to a cleaned 30 mL beaker and wash out the receiving flask with acetone. During filtration, if you see no solvents left at the receiving flask, you can add a minimum amount of ether (~5-10 mL) to dissolve the solid substance. Ether is volatile at room temperature.

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, Chem 215 spring08. OpenStax CNX. Mar 21, 2008 Download for free at http://cnx.org/content/col10496/1.8
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