COURSE : ORGANIC
CHEMISTRY I
CREDIT : 3 SKS
DAY/ TIME :
TUESDAY, NOVEMBER 13TH 2012-11-13
LECTURE :
Dr. Syamsurizal
NAME :
MUHAMMAD HAQIQI
NIM :
RSA1C111O12
1 A. Explain
how the concept of organic compounds from petroleum can be used as a fuel for
vehicles such as car , motor bike , including aricraft .
B Explain
it how the idea of chemical compounds of petroleum can be used to make clothing
and plastic and materials needs of other human lives .
2. Explain why
the hydrocarbon asymetrical or chiral have a variety of benefit for human being
. and describe how does it the chiral centers can be formed .
3. When ethylene gas produced from a ripe fruit can be used to ripe other
fruits that are still unripe . how do you idea when the gas is used as fuel gas
like methane gas.
4. Aromatic
compounds are marked by ease of adjacent electrons conjugated . please explain
why an unsaturated compund which highly conjugated but is not aromatic ?
Answer
1. A.
The alkanes, also known
as paraffins, are saturated hydrocarbons with straight
or branched chains which contain only carbon and hydrogen and
have the general formula CnH2n+2. They generally have
from 5 to 40 carbon atoms per molecule, although trace amounts of shorter or
longer molecules may be present in the mixture.
The alkanes from pentane (C5H12)
to octane (C8H18)
are refined into petrol, the ones from nonane (C9H20)
to hexadecane (C16H34)
into diesel fuel,kerosene and jet fuel.
Alkanes with more than 16 carbon atoms can be refined into fuel oil and lubricating
oil. At the heavier end of the range, paraffin wax is
an alkane with approximately 25 carbon atoms, while asphalt has
35 and up, although these are usually cracked by modern refineries into
more valuable products. The shortest molecules, those with four or fewer carbon
atoms, are in a gaseous state at room temperature. They are the petroleum
gases. Depending on demand and the cost of recovery, these gases are either flared off,
sold as liquified petroleum gas under
pressure, or used to power the refinery's own burners. During the winter,
butane (C4H10), is blended into the petrol pool at high
rates, because its high vapor pressure assists with cold starts. Liquified
under pressure slightly above atmospheric, it is best known for powering
cigarette lighters, but it is also a main fuel source for many developing
countries. Propane can be liquified under modest pressure, and is consumed for
just about every application relying on petroleum for energy, from cooking to
heating to transportation.
The cycloalkanes, also
known as naphthenes, are saturated hydrocarbons which have one or
more carbon rings to which hydrogen atoms are attached according to the formula
CnH2n. Cycloalkanes have similar properties to alkanes
but have higher boiling points.
The aromatic hydrocarbons are unsaturated hydrocarbons which have
one or more planar six-carbon rings called benzene rings,
to which hydrogen atoms are attached with the formula CnHn.
They tend to burn with a sooty flame, and many have a sweet aroma. Some are carcinogenic.
These different molecules are
separated by fractional distillation at an oil
refinery to produce petrol, jet fuel, kerosene, and other hydrocarbons. For
example, 2,2,4-trimethylpentane (isooctane),
widely used in petrol, has a chemical formula of C8H18 and
it reacts with oxygen exothermically:[18]
2 C8H18(l) +
25 O2(g) → 16 CO2(g) +
18 H2O(g) (ΔH = −10.86 MJ/mol of octane)
The amount
of various molecules in an oil sample can be determined in laboratory. The
molecules are typically extracted in a solvent,
then separated in a gas
chromatograph, and finally determined with a suitable detector,
such as a flame ionization detector or a mass
spectrometer.[19] Due
to the large number of co-eluted hydrocarbons within oil, many cannot be
resolved by traditional gas chromatography and typically appear as a hump in
the chromatogram. This unresolved complex mixture (UCM) of
hydrocarbons is particularly apparent when analysing weathered oils and
extracts from tissues of organisms exposed to oil.
Incomplete
combustion of petroleum or petrol results in production of toxic byproducts.
Too little oxygen results in carbon
monoxide. Due to the high temperatures and high pressures involved,
exhaust gases from petrol combustion in car engines usually include nitrogen
oxides which are responsible for creation of photochemical smog.
Petroleum Can be formed as a fuel
for vehicles is The range of carbon chain: C6 to C11
Boiling Route: 50 to 85 ° C
Gasoline obtained from the
distillation of petroleum caused many knock (knocking). The knock caused the
"self ignition", which combustion occurs too quickly before the
piston is in the right position. The more beats, the less efficient use of fuel
and can damage the engine therefore only burn gasoline in the vapor phase, the
gasoline must be vaporized in the carburetor before being burned in the engine
cylinder. The energy generated from the combustion of gasoline is converted
into motion through the following steps.
Burning gasoline is desired that
produces a smooth impetus to the decline of the piston. It depends on the
timeliness of combustion so that the amount of energy transferred to a maximum
piston. Timeliness combustion depending on the type of hydrocarbon chains which
in turn will determine the quality of gasoline.
Octane Numbers
Inside the machine, a mixture of air
and fuel (a gas) is pressed by the piston to a very small volume and then set
on fire by sparks produced plugs. Because they magnitude of this pressure, the
air fuel mixture can ignite spontaneously before the spark from the spark plug
out. Octane number of the gasoline to provide information to us about how much
pressure the bias given before the gasoline ignites spontaneously. If the gas
mixture is ignited due to the high pressure (and not because of the spark
plugs), there will be a knock or knock in the engine. This will cause engine
knocking easily damaged, so this should be avoided.
Name derived from octane octane
(C8), because of all the molecules making up petrol, octane has the best
compression properties, octane can be compressed to a small volume without
experiencing spontaneous combustion, not as happens in heptane, for example, which
can ignite spontaneously although freshly pressed slightly .
Gasoline with 87 octane, the fuel
consists of 87% octane and 13% heptane (or a mixture of other molecules).
Gasoline will ignite spontaneously at a certain compression level numbers given
that only meant that the vehicle's engine has a compression ratio that does not
exceed that number.
Gasoline is a petroleum distillate
having a low octane number (<60), because it consists mainly straight-chain
alkanes. Low octane number can be increased by adding anti-knock additive
substance that processes the conversion of straight-chain alkanes into branched
chain. Anti-knock substances that have been used include:
a. Tetra Ethyl Lead (TEL)
Molecular formula Pb (C2H5) 4. TEL
was banned for use as current use in gasoline combustion can produce lead oxide
(PbO) attached to the engine components. Agar (PbO) does not stick to the use
of TEL (65%) was added to 1,2-dibromo ethane and 1,2-dichloro ethane that turns
into PbBr2 Pb (volatile) coming out of the exhaust. These substances can
pollute the air and if it enters the body will result in anemia, headache, and
when in high levels can cause death.
b. Ethyl Tertiary Butyl Ether (ETBE)
Molecular formula CH3O (C2H5) 3
c. Tertiary amyl methyl ether (TAME)
Molecular formula CH 3 O (CH3) C2H5
d. Methyl Tertiary Butyl Ether
(MTBE)
Molecular formula CH3O (CH3) 3
Additive most widely used to date.
However, its use is also limited because of toxic and cancer-causing. Premix
gasoline using a mixture of MTBE and TEL.
Exhaust fumes may produce CO, CO2,
SO2 and NOx. Gas COsangat dangerous if inhaled too much can lead to death,
because disturb the binding of oxygen by hemoglobin.
1.b
Establishment
of clothing, plastics and other materials (naphtha) that humans need of
petroleum refining occurs in the fourth fraction of the processing of the first
distillation of petroleum with a rise in temperature of less than 200 degrees
Celsius. In this route, naphtha (gasoline by weight) will melt and come out to
the shelter naphtha. Naphtha is a mixture of alkanes with chain C9H20-C12H26
In subsequent processing to get
results without material adverse human made chemical processes such as
cracking, polymerase, and reform.
The trick can be implemented as
follows:
• Thermal Cracking, ie cracking
process using high temperature and pressure only.
• Cracking catalytic, ie cracking
process using heat and catalysts to convert distillate that has a high boiling
point into gasoline and karosin. This process will also produce butane and
other gases.
• Cracking with hydrogen
(hydro-cracking), ie cracking process which is a combination of thermal and
catalytic cracking to "inject" hydrogen molecule unsaturated
hydrocarbon fraction. In this way, it can be produced from petroleum LPG,
naphtha, karosin, jet fuel, and diesel. Amount obtained will be more and better
quality than the thermal cracking process or catalytic cracking alone. In
addition, the residual amount will be reduced
Polymerization is a merger of two or
more molecules to form single molecules called polymers. Polymerization goal
was to combine hydrocarbon molecules in a gas (ethylene, propene) to a compound
of light naphtha.
Reformation
This process can be a mild thermal
cracking of naphtha to obtain a more volatile products such as olefins with a
higher octane number. In addition, it can also be the catalytic conversion of
naphtha components untukmenghasilkan aromatic with a higher octane number
Hydrocarbons
chiral forms are beneficial to humans because hydrocarbons have optical
isomers. Optical isomers are isomers caused by different directions of rotating
the plane of polarization of light. Active optical properties of a compound due
to the asymmetric C atom (ie C atoms that bind four different atoms or groups)
* Dekstro
(d) turn to the right (clockwise)
* Levo (l)
turn to the left (counter clockwise)
Chiral
compounds are formed because it has an asymmetric C atom, the C atom that binds
to 4 atoms / groups of different atoms, has a pair of optical isomers. This is
caused by the ability of these compounds rotate plane polarized light. Rotation
to the left labeled l (levo = levus) and rotation to the right mark d (dekstro
= dekster). For example, 2-hydroxy propanoic acid, CH3CHOHCOOH. Atom C no. (2)
binding H, OH, CH3, and COOH. C atom is called asymmetric or chiral. Couple
isomer (d) and (l) is called enantiomer pair. This isomer pair one being the mirror
image of the other.
3.
Ethylene
(ethene H2C = H2) with molecular weights 28.0536 an olefinic hydrocarbons are
the lightest, colorless liquid, flammable gas, smelling sweet. These compounds
contained in natural gas, petroleum dirty, or other fossil fuel deposits.
However, ethylene can also be obtained in large quantities from a variety of
thermal and catalytic processes with high temperature fractions of natural gas
and petroleum as a raw material. Ethylene glycol or called Monoetilen Glycol,
resulting from the reaction of ethylene oxide with water, an antifreeze agent
used on the machines, also used for the production of raw materials
polietilenterephthalate (PET) and as a liquid heat exchanger. Ethylene glycol
is an organic compound that can lower the freezing point of the solvent to
disrupt the formation of ice crystals solvent. Ethylene Glycol is a liquid
saturated, colorless, odorless, sweet taste, and dissolve completely in water.
Commercially, ethylene glycol in Indonesia are used as raw material for
polyester industry (textiles) of 97.34%. Ethylene Glycol (1,2-etandiol,
HOCH2CH2OH) by Mr 62.07 is a simple diol compounds. Ethylene Glycol in the form
of a colorless liquid with a sweet aroma. The compound is hygroscopic and
dissolve completely in various polar solvents such as water, alcohols, glycol
ethers, and acetone. Slightly soluble in nonpolar solvents, such as benzene,
toluene, dikloroetan, and chloroform. Ethylene glycol is hard crystallized when
cold, he shaped compound that is very thick (viscous)
Reaction
etilene with oxygen
To my knowledge we can use ethylene gas as antifreeze
in cars. But I think if it is used as fuel could have happened when we
reaksikan with oxygen. But the quality of the fuel produced is not necessarily
better than methane. Gases such as carbon dioxide produced can be so much more
than the amount of methane and ethylene gas heat generated is less than that of
methane. Unless processed again to produce more heat. But it has been proven
fuel methane gas is more environmentally friendly than other hydrocarbon
materials
4.
Based on the arrangement of carbon atoms in the molecule, carbon compounds are divided into two major categories, namely compound aliphatic and cyclic compounds. Aliphatic hydrocarbons are carbon compounds chain opens its C and C it allows branched chain. Based on the amount of the bond, aliphatic hydrocarbons, aliphatic compounds are divided into saturated and unsaturated.
- The compound is a saturated aliphatic C chain aliphatic compounds it contains only single bonds only. This group is called alkanes.
Unsaturated aliphatic compounds are aliphatic compounds, varying chain C double bond or triple. If you have duplicate named alkenes and alkynes have triple called. In unsaturated compounds (-C = O), the transition to the low-energy non-bonding involves electrons to oxygen, one of it was promoted to the p * orbital which is relatively low. However, the transition from n to p *, called "forbidden" or including a ban on the transition, it is associated with a low intensity. Two others, namely the transition from n to s * and from p to s *. Both give strong absorption, but involves high energy. The most noticeable absorption intensity for ketone compounds are electron transition p to p *
Based on the arrangement of carbon atoms in the molecule, carbon compounds are divided into two major categories, namely compound aliphatic and cyclic compounds. Aliphatic hydrocarbons are carbon compounds chain opens its C and C it allows branched chain. Based on the amount of the bond, aliphatic hydrocarbons, aliphatic compounds are divided into saturated and unsaturated.
- The compound is a saturated aliphatic C chain aliphatic compounds it contains only single bonds only. This group is called alkanes.
Unsaturated aliphatic compounds are aliphatic compounds, varying chain C double bond or triple. If you have duplicate named alkenes and alkynes have triple called. In unsaturated compounds (-C = O), the transition to the low-energy non-bonding involves electrons to oxygen, one of it was promoted to the p * orbital which is relatively low. However, the transition from n to p *, called "forbidden" or including a ban on the transition, it is associated with a low intensity. Two others, namely the transition from n to s * and from p to s *. Both give strong absorption, but involves high energy. The most noticeable absorption intensity for ketone compounds are electron transition p to p *
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