S6 Project : Making model of molecules

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S6 Project Making model of molecules
Aim The aim of this project to make one simple
molecule structure as well as one form of
allotropes of carbon. During construction, the
concept of hybridization, electron pair repulsion
theory, bond angle and molecular shape could be
reinforced and clarified.
Our Model 1 Benzaldehyde Our Model 2
Graphite Our Model 3 Fullerence C60 Structural
formulae Further information of Benzaldehyde Data
Sources
Members Cheung Yuk Kam (8), Lee Wai Ki (20),
Tang Ho Yan (28)
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Our Model 1 Benzaldehyde
Benzaldehyde (C6H5CHO) is a chemical compound
consisting of a benzene ring with an aldehyde
substituent. It is the simplest representative of
the aromatic aldehydes and one of the most
industrially used members of this family of
compounds. At room temperature it is a colorless
liquid with a characteristic and pleasant
almond-like odor benzaldehyde is an important
component of the scent of almonds hence its
typical odor. It is the primary component of
bitter almond oil extract, and can be extracted
from a number of other natural sources in which
it occurs, such as apricot, cherry, and laurel
leaves, peach seeds and, in a glycoside combined
form (amygdalin), in certain nuts and kernels.
Currently benzaldehyde is primarily made from
toluene by a number of different processes.
C
The hydrogen atom is sp3 hybridised. The other
atoms are sp2 hybridised. C-C bond length
0.154 nm CC bond length 0.134 nm C-H bond
length 0.109 nm CO bond length 0.116 nm
O
H
Further information of Benzaldehyde
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Our Model 2 Graphite
Carbon have two allotrope, diamond and graphite.
Graphite make up of hexagonal arrays of carbon
atoms arranged in layers.
Within each layer, each carbon atom is bonded
with three other carbon atoms by C-C covalent
bonds. Because of the partial double bond
character of the C-C bond in graphite, the carbon
atoms are said to be sp2 hybridised. The bonded
planar trigonally to three other carbon atoms by
single dcovalent bonds.
A network of coplanar hexagons is formed, with A
C-C bond length of 0.142nm, which is intermediate
between a C-C single bond(0.154nm) and a CC
double double bond(0.134nm). This is because the
C-C bond in graphite is formed by overlapping of
2 sp2 hybrid orbitals of carbon and
delocalisation of electrons by overlapping of the
unhybridised p orbitals of the carbon atoms.
Since adjacent layers of the graphite are held
together by van der Waals forces, the distance
between separate layers is much longer(0.34nm).
And this allow the layers to slide over each
other easily.
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Our Model 3 Fullerence C60
C60 have 60 Carbon atoms which can be considered
to be equivalent. Hybridisation of somewhat
between sp3 and sp2. Thy do not form straight
bonds directed at 120? to each other as that
would only form an infinite plane and cannot be
folded into a stable curved structure like a
soccer ball.
The C60 structure represents a third form of
allotrope of crystalline carbon. C60 is soluble
in various organic solvents such as hexane. It
can conduct electricity due to the present of
delocalised electrons on their surface.
C60 can act as lubricants, superconductors,
rocket fuels, lasers, batteries, magnetic films,
cancer and AIDS drugs
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Structural formulae
Phenyl ethanoate C8H8O2
Benzadehyde C6H5CHO
N-methyethanmide
Phenylethene (styrene) C8H8
Propenal C2H3CHO
Aminoethanoic acid (glycine) C2H5NO2
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Further information of Benzaldehyde
How to prepare Benzaldehyde?
Benzaldehyde a typical aromatic aldehyde can be
obtained from methylbenzene either by selective
oxidation or by dihalogenation in the side chain
and subsequent hydrolysis.
Chemical properties of Benzaldehyde
Benzaldehye resembles aliphatic aldehydes having
no alkyl hytrigen atom adjacent to the
delocalised p-electrons of he benzene ring tend
tolower the positive charge on the carbon atom of
the CO bond so that it is less easily attacked
by nucleophiles. The benzene ring also inhibits
nucleophilic attackby steric hindrance. The main
distinctive property of benzaldehyde is that it
will dimerise hydroxy-1,2-diphenylethanone(benzoin
).
Application of Benzaldehyde
While it can be employed as a solvent,
benzaldehyde is used chiefly in the synthesis of
other organic compounds, ranging from
pharmaceuticals to plastic additives. It is also
an important intermediate for the processing of
perfume and flavouring compounds and in the
preparation of certain aniline dyes.
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Data Sources
Websites
Wikipedia http//en.wikipedia.org/wiki/Main_Page
Sample Slides http//www.ecsel.psu.edu/snathan/jb
/index.html
UWCAEA http//www.uwcsea.edu.sg/
Books
Organic chemistry (Brief course) Harland
D. Embree Organic Chemistry sixth edition
Morrison Boyd Prentice-Hall International
edition A New introduction to organic chemistry
Cl Brown