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• CARBON is the chemical element withsymbol C and atomic number 6. As amember of group IV on the periodictable, it is nonmetallic and tetravalent—making four electrons available to• form covalent chemical bonds.

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Some Physical Properties of Carbon

Atomic number: 6

Atomic mass: 12.0107 amu

Melting Point: 3,823 K

Boiling Point: 4,098 K

Density: 2.2670 g/cm3

Phase (room temp.): Solid

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Types of Covalent Bond

•Single Covalent Bond :mutual sharing of one pair of electrons.

•Double Covalent Bond :mutual sharing of two pair of electrons.

•Triple Covalent Bond :mutual sharing of three pair of electrons.

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Eg. :- Formation of single covalent bond in Hydrogen molecule - H2

The atomic number of hydrogen is 1, its electronic arrangement is 1, it has 1 valence electron. It needs 1 electron more to attain stability. So two hydrogen atoms share 1 pair of electrons resulting in the formation of a single covalent bond in hydrogen molecule H2.

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Formation of double covalent bond in oxygen molecule - O2

The atomic number of oxygen is 8, its EC is 2,6, it has 6 VE, it needs 2 electrons more to attain stability. So two oxygen atoms share two pairs of electrons resulting in the formation of a double covalent bond in oxygen molecule O2.

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Formation of triple covalent bond in Nitrogen molecule - N2

The atomic number of nitrogen is 7, its EC is 2,5, it has 5 VE, it needs 3 electrons more to attain stability. So two nitrogen atoms share three pairs of electrons resulting in the formation of a triple covalent bond in nitrogen molecule N2.

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• Low Melting and boiling point.

• Physical State (liquid or gas)

• Low Density.

• Solubility.

• Bad Conductor of Electricity.

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Covalent Compounds

• Insoluble in water.

• Gaseous, liquids or soft solids.

• Low boiling and melting point.

• Soluble in organic solvents.

Ionic Compounds

• Soluble in water.

• Crystalline solids.

• High boiling and melting point.

• Insoluble in organic solvents.

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Allotropes of Carbon Two or more forms of

the same element that

differ significantly

in chemical & physical

properties are known

as allotropes.

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Graphite is derived from the Greek word“graphein” which means to write. It wasnamed by the German Geologist AbrahamWerner in 1789.

Graphite

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Diamond

In diamond, each carbon atom is tetra headedly attached to four other carbon atoms forming a rigid three dimensional structure. Thus it is the hardest substance known.

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• Fullerene research is expected to lead to newmaterials, lubricants, coatings, catalysts, electro-optical devices, and medical applications.

• First identified in 1985 by R. F. Curl, Jr., R. E.Smally, and H. W. Kroto (who shared the 1996Nobel Prize in Chemistry)

Fullerenes

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Organic Chemistry: The branch of chemistry dealing with carbon compounds, other than CO , CO2 and carbonates, is called Organic Chemistry.

Organic compounds: The compounds of carbon, other than CO , CO2 and carbonates, are called Organic Compounds

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IsomerismCompounds having the same molecular formulae butdifferent structural arrangement of atoms in themare known as isomers, and the phenomenon is known asisomerism.

Examples of Isomerism:

Butane – C4H10 has 2 isomers.

They are Normal butane and

Iso butane.

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SATURATED HYDROCARBON

UNSATURATED HYDROCARBON

Compounds of carbon in which their molecules are composed

of only carbon and hydrogen atoms are called hydrocarbons.

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•A Hydrocarbon is an organic compound thatcontains only the elements hydrogen and carbon.•In a saturated hydrocarbon, all the bonds aresingle bonds.•Alkane is another name for asaturated hydrocarbon.

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Examples of Saturated Hydrocarbons

Ethane C2H6

Propane C3H8

Butane C4H10

Examples of Saturated Hydrocarbons

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A hydrocarbon that contains one or more double or triple bonds is an unsaturated hydrocarbon. There are three types of unsaturated hydrocarbons : Alkenes , Alkynes & Aromatic hydrocarbons .

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Examples of Unsaturated Hydrocarbons

Ethene C2H4

Propane C3H6

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Systematic Nomenclature of Carbon

Compounds

Number of carbon atoms in the parent chain

Root word

1 Meth

2 Eth

3 Prop

4 But

5 Pent

6 Hex

7 Hept

8 Oct

9 Non

10 Dec

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Homologous series

A homologous series is a group of organic compounds having similar structures and similar chemical properties in which the successive compounds differ by CH2 group

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Characteristics

-) All members of homologous series can be represented by the same general formula .-) All compound show similar chemical properties .

-) The members of homologous series show a gradual change in their physical properties with increase in molecular mass .

-) Any two adjacent homologues differ by 1 carbon atom and 2 hydrogen atom in their molecular formulae ...

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Alkanes

The general formula of alkanes is CnH2n+2 where n is no. of carbon atoms in 1 molecule of alkanes.Single Bond……

ALKANE MOLECULAR FORMULA

Methane CH4

Ethane C2H6

Propane C3H8

Butane C4H10

pentane C5H1224

Alkenes Molecular formula

Ethene C2H4

Propene C3H6

Butene C4H8

Pentene C5H10

Hexene C6H12

ALKENES

The general formula of alkenes is CnH2n where n is no. of carbon atoms in 1 molecule of alkenes.At least 1 Double Bond……

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ALKYNE MOLECULARFORMULA

Ethyne C2H2

Propyne C3H4

Butyne C4H6

Pentyne C5H8

Hexyne C6H10

ALKYNESThe general formula of alkyne is CnH2n-2

where n is no. of carbon atoms in 1 molecule of alkyne.

At least 1 Triple Bond……

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FUNCTIONAL GROUPSIn organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical

reactions of those molecules.

FUNCTIONAL GROUPS SUFFIX / PREFIX

& SYMBOLS

ALDEHYDE Suff – ‘al’

ALCOHOL Suff – ‘ol’

KETONE Suff–‘one’

CARBOXYLIC ACID Suff – ‘oic acid’

HALOGEN Pref – chloro , bromo, floro, iodo

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SoapsSoaps :-Soaps are long chain sodium or potassium salts of carboxylic acids.

Eg:- Sodium stearate – C17H35COONa

Structure of soap molecule :-

A soap molecule has two parts. A long hydrocarbon part which is

hydrophobic (water repelling) and soluble in oil and grease and a

short ionic part which is hydrophyllic (water attracting) and

insoluble in oil and grease.

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Cleansing Action of Soap

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Differences between soaps and detergents

Soaps Detergents

Soaps are sodium salts of fatty acids.

Detergents are sodium salts of sulphonic acids.

Soaps clean well in soft water but do not clean well in hard water.

Detergents clean well with both hard and soft water.

Soaps do not clean as much as detergents.

Detergents clean better than soaps.

Soaps are biodegradable and do not cause pollution.

Some detergents are non biodegradable and cause pollution.

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