Alkanes: chemistry

Alkane

What is Alkane?

The simplest members of Organic Compounds are known as Alkanes.

Alkanes are made up of carbon and hydrogen atoms only; and hence are called Hydrocarbons. The name hydrocarbon describes the composition of alkanes; and hence the name Hydrocarbons becomes more relevant name for alkanes.

All of the four valency of carbon atoms in an Alkanes are satisfied; so alkanes are known as Saturated Hydrocarbons.

Alkanes are also known as PARAFFINS. Paraffins is the combination of two Latin words 'Parum + affinis'. Where 'Parum' means 'barely or little or less' and 'affinis' means 'lacking affinity'. The complete meaning of the term 'Paraffins' is 'Lacking affinity' or 'Lacking Reactivity'.

Since Alkanes are relatively unreactive under normal laboratory conditions, so they got name as Paraffins.

Constituent Elements of Alkanes

Alkanes are made of elements of carbon and hydrogen only. This leads their name as Hydrocarbon.

Types of bond in Alkanes

In Alkanes (Saturated Hydrocarbons or Parrafins) only single covalent bonds are present. These single covalent bonds are of two types:

(a) "Carbon—Carbon (C—C)" single covalent bonds, and

(b) "Carbon—Hydrogen (C—H)" single covalent bonds.

Alkanes do not have any functional group.

Examples of Alkanes: Methane (CH₄), Ethane (C₂H₆), Propane (C₃H₈), etc. are examples of Alkanes.

In IUPAC system of naming, Alkane is used as generic name for members of Saturated Hydrocarbons.

General Formula of Alkanes

The general formula of Alkanes is C_nH_2n+2.

Where, n = number of carbon atoms

Examples:

(1) If n = 1

∴ C_nH_{2n + 2}

= C₁H_{2 x 1 + 2} = CH₄

Alkane (Saturated Hydrocarbon) having one carbon atom is called METHANE

(2) If n = 2

∴ C_nH_{2n + 2}

= C₂H_{2 x 2 + 2} = C₂H₆

Alkane (Saturated Hydrocarbon) having two carbon atoms is called ETHANE

(3) If n = 3

∴ C_nH_{2n + 2}

= C₃H_{2 x 3 + 2} = C₃H₈

Alkane (Saturated Hydrocarbon) having two carbon atoms is called PROPANE

(4) If n = 4

∴ C_nH_{2n + 2}

= C₄H_{2 x 4 + 2} = C₄H₁₀

Alkane (Saturated Hydrocarbon) having two carbon atoms is called BUTANE

Here, the prefix 'buta' means four. Thus, this compound is named as Butane.

In the name of this caompound, 'Buta' means four and 'ane' exists for alkane.

(5) Similarly, alkane with five carbon atoms is known as Pentane (C₅H₁₂)

Here, the prefix penta– means five.

(6) Alkane with six carbon atoms is known as Hexane (C₆H₁₄)

Here, the prefix hexa– means six.

(7) Alkane with seven carbon atoms is known as Heptane (C₇H₁₆)

Here, the prefix hepta– means seven.

(8) Alkane with eight carbon atoms is known as Octane (C₈H₁₈)

Here, the prefix octa– means eigth. As prefix octa is found in Octopus, means animal with eight feet.

(9) Alkane with nine carbon atoms is known as Nonane (C₉H₂₀)

Here, the prefix nona– means nine.

(10) Alkane with ten (10) carbon atoms is known as Decane (C₁₀H₂₂)

Here, the prefix deca– means ten.

Name of higher alkanes

(11) Alkane with eleven (11) carbon atoms is known as undecane (C₁₁H₂₄)

(12) Alkane with twelve (12) carbon atoms is known as dodecane (C₉H₂₀)

(13) Alkane with thirteen (13) carbon atoms is known as tridecane (C₁₃H₂₈)

(14) Alkane with fourteen (14) carbon atoms is known as tetradecane (C₁₄H₃₀)

(15) Alkane with fifteen (15) carbon atoms is known as pentadecane (C₁₅H₃₂)

(16) Alkane with sixteen (16) carbon atoms is known as hexadecane (C₁₆H₃₄)

(17) Alkane with seventeen (17) carbon atoms is known as heptadecane (C₁₇H₃₆)

(18) Alkane with eighteen (18) carbon atoms is known as octadecane (C₁₈H₃₈)

(19) Alkane with nineteen (19) carbon atoms is known as nonadecane (C₁₉H₄₀)

(20) Alkane with twenty (20) carbon atoms is known as icosane (C₂₀H₄₂)

(21) Alkane with twentyone (21) carbon atoms is known as henicosane (C₂₁H₄₄)

(22) Alkane with twentytwo (22) carbon atoms is known as docosane (C₂₂H₄₆)

(23) Alkane with twentythree (23) carbon atoms is known as tricosane (C₂₃H₄₈)

(24) Alkane with twentyfour (24) carbon atoms is known as tetracosane (C₂₄H₅₀)

(25) Alkane with twentyfive (25) carbon atoms is known as pentacosane (C₂₅H₅₂)

(26) Alkane with twentysix (26) carbon atoms is known as hexacosane (C₂₆H₄₄)

(27) Alkane with twentyseven (27) carbon atoms is known as heptacosane (C₂₇H₅₆)

(28) Alkane with twentyeight (28) carbon atoms is known as octacosane (C₂₈H₅₈)

(29) Alkane with twentynine (29) carbon atoms is known as nonacosane (C₂₉H₆₀)

(30) Alkane with thirty (30) carbon atoms is known as triacontane (C₃₀H₆₂)

(31) Alkane with thirtyone (31) carbon atoms is known as hentriacontane (C₃₁H₆₄)

(32) Alkane with thirtytwo (32) carbon atoms is known as dotriacontane (C₃₂H₆₆)

(33) Alkane with thirtythree (33) carbon atoms is known as tritriacontane (C₃₃H₆₈)

(34) Alkane with thirtyfour (34) carbon atoms is known as tetratriacontane (C₃₄H₇₀)

(36) Alkane with thirtyfive (35) carbon atoms is known as pentatriacontane (C₃₅H₇₂)

(37) Alkane with thirtysix (36) carbon atoms is known as hexatriacontane (C₃₁H₆₄)

(38) Alkane with thirtyeight (38) carbon atoms is known as heptatriacontane (C₃₈H₇₈)

(39) Alkane with thirtynine (39) carbon atoms is known as nonatriacontane (C₃₉H₈₀)

(40) Alkane with forty (40) carbon atoms is known as tetracontane (C₄₀H₈₂)

In similar way alkane with carbon atoms equal to 41 will be named as prefix hen + name of alkane with 40 carbon atoms. Such as "hentetracontane"

Alkane with carbon atoms equal to 42 will be named as prefix do + name of alkane with 40 carbon atoms. Such as "dotetracontane"

Alkane with carbon atoms equal to 43 will be named as prefix tri + name of alkane with 40 carbon atoms. Such as "tritetracontane" and so on.

(41) Alkane with fifty (50) carbon atoms is known as pentacontane (C₅₀H₁₀₂)

In similar way alkane with carbon atoms equal to 51 will be named as prefix hen + name of alkane with 50 carbon atoms. Such as "henpentacontane"

Alkane with carbon atoms equal to 52 will be named as prefix do + name of alkane with 50 carbon atoms. Such as "dopentacontane"

Alkane with carbon atoms equal to 53 will be named as prefix tri + name of alkane with 50 carbon atoms. Such as "tripentacontane" and so on.

(42) Alkane with sixty (60) carbon atoms is known as hexacontane (C₆₀H₁₂₂)

In similar way alkane with carbon atoms equal to 61 will be named as prefix hen + name of alkane with 60 carbon atoms. Such as "henhexacontane"

Alkane with carbon atoms equal to 62 will be named as prefix do + name of alkane with 60 carbon atoms. Such as "dohexacontane"

Alkane with carbon atoms equal to 63 will be named as prefix tri + name of alkane with 60 carbon atoms. Such as "trihexacontane" and so on.

(43) Alkane with seventy (70) carbon atoms is known as heptacontane (C₇₀H₁₄₂)

In similar way alkane with carbon atoms equal to 71 will be named as prefix hen + name of alkane with 70 carbon atoms. Such as "henheptacontane"

Alkane with carbon atoms equal to 72 will be named as prefix do + name of alkane with 70 carbon atoms. Such as "doheptacontane"

Alkane with carbon atoms equal to 73 will be named as prefix tri + name of alkane with 70 carbon atoms. Such as "triheptacontane" and so on.

(44) Alkane with eighty (80) carbon atoms is known as octacontane (C₈₀H₁₆₂)

In similar way alkane with carbon atoms equal to 81 will be named as prefix hen + name of alkane with 80 carbon atoms. Such as "henoctacontane"

Alkane with carbon atoms equal to 82 will be named as prefix do + name of alkane with 80 carbon atoms. Such as "dooctacontane"

Alkane with carbon atoms equal to 83 will be named as prefix tri + name of alkane with 80 carbon atoms. Such as "trioctacontane" and so on.

(45) Alkane with ninty (90) carbon atoms is known as nonacontane (C₉₀H₁₈₂)

In similar way alkane with carbon atoms equal to 91 will be named as prefix hen + name of alkane with 90 carbon atoms. Such as "hennonacontane"

Alkane with carbon atoms equal to 92 will be named as prefix do + name of alkane with 90 carbon atoms. Such as "dononacontane"

Alkane with carbon atoms equal to 93 will be named as prefix tri + name of alkane with 90 carbon atoms. Such as "trinonacontane" and so on.

(45) Alkane with hundred (100) carbon atoms is known as hectane (C₁₀₀H₂₀₂)

(46) Alkane with hundredone (101) carbon atoms is known as henihectane (C₁₀₁H₂₀₄)

Alkane with carbon atoms equal to 102 will be named as prefix do + name of alkane with 100 carbon atoms. Such as "dohectane"

Alkane with carbon atoms equal to 103 will be named as prefix tri + name of alkane with 100 carbon atoms. Such as "trihectane" and so on.

Alkane with carbon atoms equal to 104 will be named as prefix tetra + name of alkane with 100 carbon atoms. Such as "tetrahectane" and so on.

(47) Alkane with hundredten (110) carbon atoms is known as decahectane (C₁₁₀H₂₂₂)

(48) Alkane with hundredeleven (111) carbon atoms is known as undecahectane (C₁₁₁H₂₂₄)

Alkane with carbon atoms equal to 112 will be named as prefix do + name of alkane with 110 carbon atoms. Such as "dodecahectane"

Alkane with carbon atoms equal to 113 will be named as prefix tri + name of alkane with 110 carbon atoms. Such as "tridecahectane" and so on.

(49) Alkane with hundredeleven (120) carbon atoms is known as icosahectane (C₁₂₀H₂₄₂)

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