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May 06, 2015
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Although cells are 70-95% water, the rest
consists mostly of carbon-based compounds.
Proteins, DNA, carbohydrates, and lipids are all composed of carbon atoms bonded to each other and to atoms of other elements. These other elements commonly include
hydrogen (H), oxygen (O), nitrogen (N), sulfur (S), and phosphorus (P).
Introduction
The study of carbon
compounds, organic chemistry, focuses on any compound with carbon (organic compounds). Organic compounds can
range from the simple (CH4) to complex molecules, like proteins, that may weigh over 100,000 daltons.
Organic chemistry is the study of carbon compounds
Because of carbon’s
versatility, these few elements can be combined to
build an inexhaustible
variety of organic molecules.
With a total of 6 electrons, a carbon
atom has 2 in the first shell and 4 in the second shell. Carbon has little tendency to form
ionic bonds by losing or gaining 4 electrons.
Instead, carbon usually completes its valence shell by sharing electrons with other atoms in four covalent bonds.
Carbon atoms are the most versatile building blocks of
molecules
Carbon chains form the skeletons of
most organic molecules. The skeletons may vary in
length and may be straight, branched, or arranged in closed rings.
The carbon skeletons may also include single, double and triple bonds..
Variation in carbon skeletons contributes to the diversity of
organic molecules
Fats are biological
molecules that have long hydrocarbon tails attached to a non-hydrocarbon component.
Hydrocarbons are organic molecules that consist of only carbon and hydrogen atoms.
Isomers are compounds that have the same molecular formula but different
structures and therefore different chemical properties.
For example, butane and isobutane have the same molecular formula C4H10, but butane has a straight skeleton and isobutane has a branched skeleton.
The components of organic
molecules that are most commonly involved in chemical reactions are known as functional groups.
The number and arrangement of functional groups help give each molecule its unique properties.
Functional groups contribute to the
molecular diversity of life
Saturated Hydrocarbons
A Hydrocarbon is an organic compound that contains only the elements hydrogen and carbon.
In a saturated hydrocarbon, all the bonds are single bonds.
Alkane is another name for a saturated hydrocarbon.
Ethane
Characteristics of Hydrocarbons
Factors that determine the properties of a hydrocarbon are:
The number of carbon atoms
How the atoms are arranged:
Straight chain Branched chain Ring
Straight Chains A hydrocarbon can
contain one carbon atom, as in methane or thousands of carbon atoms, as in cellulose.
One carbon Methane
Two carbon ethane
Three carbon propane
Four carbon butane
Five carbons pentane
Six carbon hexane
Halosomers
Branched Chains The structural
formula for certain alkanes can differ.
Compounds with the same molecular formula but different structural formulas are isomers.
The Ring Carbons
can be arranged in a ring, such as cyclobutane.
Unsaturated Hydrocarbons
A hydrocarbon that contains one or more double or triple bonds is an unsaturated hydrocarbon.
There are three types of unsaturated hydrocarbons alkenes, alkynes, and aromatic hydrocarbons.
Alkenes
Many fruit bearing plants produce ethene, which controls the rate at which fruits ripening.
Alkynes Alkynes are
the most reactive hydrocarbon compounds.
They produce extremely high temperatures while burning.
Aromatic Hydrocarbons
These alternating single and double bond hydrocarbons form a ring.
Many of these compounds have strong aromas or odors.
Fossil Fuels Three types of
fossil fuels are coal, petroleum, and natural gas.
The primary products of the complete combustion of fossil fuels are carbon dioxide and water.
Substituted Hydrocarbons
The functional group in an alcohol is a hydroxyl group, -OH.
The functional group in an organic acid is a carboxyl group,-COOH.
The functional group in an amine is an amino group, -NH2
Alcohols
When a halocarbon reacts with a hydroxyl group.
Polymers Polymers can be
classified as natural polymers or synthetic polymers.
Rubber, nylon, and polyethylene are three examples of compounds than can be synthesized.
Types Four types of
polymers produced in plant and animal cells are:
Starches Cellulose Nucleic acids Proteins
Name :- Nabaneet Mondal
Class :- X “B”
Roll no. :- 20
Subject :- Science (Chemistry)
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