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ALKANES
An alkane is a saturated hydrocarbon. That means it is made of carbon and hydrogen. Carbon atoms are bonded together (all single bonds) and the remaining bonds are filled with hydrogen atoms. The formula for an alkane is **CnH2n +2** where n is the number of carbons.
 * |||| A series of organic compounds that have similar structural features but differ from adjacent members by (-CH2) group is referred to as homologous series. Each member of homologous series is called homolog. ||

 SAME structural formula  Molecular formula of different members of a homologous series differs from previous and next member by CH2.  SAME type of elements  SAME functional group  SAME general formula. ||  ALKANE : CnH2n+1  ALKENE : CnH2n  ALKYNE : CnH2n-2  ALCOHOL : CnH2n+1 OH  ETHERS : CnH2nO  Where n = number of carbon atoms. ||  Molecular mass of any two consecutive members differ by 14 units ||  SAME chemical properties || <span style="font-family: Arial,Helvetica,sans-serif;"> SAME method || <span style="font-family: Arial,Helvetica,sans-serif;"> VARYING property in atomic weight (increases) || <span style="font-family: Arial,Helvetica,sans-serif;">Boiling point increases with increasing number of carbon atoms. <span style="font-family: Arial,Helvetica,sans-serif;">Number of electrons per molecule, molecular polarizability, and contact between chains increases with increasing chain length resulting in greater intermolecular London attractive forces. || <span style="font-family: Arial,Helvetica,sans-serif;">
 * |||| **<span style="font-family: Arial,Helvetica,sans-serif;">1. STRUCTURAL FORMULA **
 * <span style="font-family: Arial,Helvetica,sans-serif;">2. MOLECULAR FORMULA **
 * <span style="font-family: Arial,Helvetica,sans-serif;"> 3. NATURE OF ELEMENT **
 * <span style="font-family: Arial,Helvetica,sans-serif;"> 4. FUNCTIONAL GROUP **
 * <span style="font-family: Arial,Helvetica,sans-serif;"> 5. GENERAL FORMULA **
 * |||| **<span style="font-family: Arial,Helvetica,sans-serif;">FOR EXAMPLE: **
 * |||| **<span style="font-family: Arial,Helvetica,sans-serif;">6. MOLECULAR MASS **
 * |||| **<span style="font-family: Arial,Helvetica,sans-serif;">7. CHEMICAL PROPERTIES **
 * |||| **<span style="font-family: Arial,Helvetica,sans-serif;">8. METHODS OF PREPARATION **
 * |||| **<span style="font-family: Arial,Helvetica,sans-serif;">9. PHYSICAL PROPERTIES **
 * || **<span style="font-family: Arial,Helvetica,sans-serif;">10. BOILING POINTS **

<span style="font-family: Arial,Helvetica,sans-serif;">What are Isomers? <span style="font-family: Arial,Helvetica,sans-serif;">- Isomers are molecules which have the same molecular formula but have different arrangement of atoms.

<span style="font-family: Arial,Helvetica,sans-serif;">Kinds of isomers: <span style="font-family: Arial,Helvetica,sans-serif;">-occurs when two or more organic compounds have the same molecular formulae, but different structures. These differences tend to give the molecules different chemical and physical properties. <span style="font-family: Arial,Helvetica,sans-serif;">3 types of structural isomerism: <span style="font-family: Arial,Helvetica,sans-serif;">- also called nuclear isomerism <span style="font-family: Arial,Helvetica,sans-serif;">-occurs when how the carbon atoms are linked together is different for different compounds to compounds.
 * <span style="font-family: Arial,Helvetica,sans-serif;">a.) Structural **
 * <span style="font-family: Arial,Helvetica,sans-serif;">1.) chain isomerism **


 * <span style="font-family: Arial,Helvetica,sans-serif;">2.) positional isomerism **
 * <span style="font-family: Arial,Helvetica,sans-serif;">occurs when functional groups are in different positions in the same carbon chain.


 * <span style="font-family: Arial,Helvetica,sans-serif;">3.) functional isomerism **
 * <span style="font-family: Arial,Helvetica,sans-serif;">substances have the same molecular formula but different functional groups. This means that functional isomers belong to different homologous series.

<span style="font-family: Arial,Helvetica,sans-serif;">-occurs when the atoms in a molecule have different arrangements in space.
 * <span style="font-family: Arial,Helvetica,sans-serif;">b.) Stereo-isomerism **

<span style="font-family: Arial,Helvetica,sans-serif;">2 types of stereoisomerism <span style="font-family: Arial,Helvetica,sans-serif;"> This can occur when: <span style="font-family: Arial,Helvetica,sans-serif;">-same chemical and physical properties but the other structure rotates to the right and the other structure rotates to the left. <span style="font-family: Arial,Helvetica,sans-serif;">- the isomers of the molecules are mirror images of themselves.
 * <span style="font-family: Arial,Helvetica,sans-serif;">a.) Geometrical isomerism **
 * <span style="font-family: Arial,Helvetica,sans-serif;">have different physical properties but have the same chemical properties.
 * <span style="font-family: Arial,Helvetica,sans-serif;">where there is a C=C bond in the molecule;
 * <span style="font-family: Arial,Helvetica,sans-serif;">where a molecule has rings; or
 * <span style="font-family: Arial,Helvetica,sans-serif;">where there is a >C=N bond.
 * <span style="font-family: Arial,Helvetica,sans-serif;">b.) optical isomerism **

<span style="font-family: Arial,Helvetica,sans-serif;">The boiling points of alkenes are dependent on the intermolecular forces that act in between them. Van der waal’s/ London forces/ Dispersion forces/ Weak intermolecular forces. As the molecular mass increases, the boiling point also increases.
 * <span style="font-family: Arial,Helvetica,sans-serif;">Reactions of Alkanes:

<span style="font-family: Arial,Helvetica,sans-serif;"> Happens when there is sufficient amount of oxygen. The end product for complete combustion of any hydrocarbon produces carbon dioxide and water.
 * <span style="font-family: Arial,Helvetica,sans-serif;"> a. Complete Combustion **

<span style="font-family: Arial,Helvetica,sans-serif;"> Propane and Oxygen, Balanced <span style="font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;"> Butane and Oxygen, Balances || <span style="font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;"> Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbours and turn to a gas.
 * <span style="font-family: Arial,Helvetica,sans-serif;">Trends: ||

<span style="font-family: Arial,Helvetica,sans-serif;">If the combustion is complete, all the hydrocarbons of the alkane will burn with a BLUE flame. As the number of carbon atoms in the molecules increases, complete combustion tends to be LESS complete.

<span style="font-family: Arial,Helvetica,sans-serif;">Bigger hydrocarbon = yellow flame

<span style="font-family: Arial,Helvetica,sans-serif;"> Happens when there is not enough oxygen present. The end product for incomplete combustion of any hydrocarbon produces carbon or carbon monoxide.
 * **<span style="font-family: Arial,Helvetica,sans-serif;">b. Incomplete Combustion ** ||

<span style="font-family: Arial,Helvetica,sans-serif;"> The presence of glowing carbon particles in a flame turns it yellow, and black carbon is often visible in the smoke. Carbon monoxide is produced as a colourless poisonous gas.


 * <span style="font-family: Arial,Helvetica,sans-serif;">c. Reaction of Alkanes with Chlorine and Bromine **

<span style="font-family: Arial,Helvetica,sans-serif;">There is no reaction between alkanes and chlorine or bromine when in the dark, but in the presence of a flame, it will produce a mixture of carbon and the hydrogen halide.

<span style="font-family: Arial,Helvetica,sans-serif;">Alkanes have low reactivity since they only have single C-C bonds. There is a test called a bromine test which is used to determine if the organic compound contains any double C=C bonds but since alkanes only contain single C-C bonds, then it will not react with bromine. The alkane will just dilute the red-brown color of bromine to an orange or yellow color in the absence of light or heat which act as a catalyst and will produce alkyl bromide.
 * || <span style="font-family: Arial,Helvetica,sans-serif;">light ||  ||
 * <span style="font-family: Arial,Helvetica,sans-serif;">CH4(g) +Br2(l) || <span style="font-family: Arial,Helvetica,sans-serif;"> → || <span style="font-family: Arial,Helvetica,sans-serif;">CH3Br(g) +HBr(g) ||

<span style="font-family: Arial,Helvetica,sans-serif;">The red brown color of bromine (Left) alkane + bromine which has no reaction

<span style="font-family: Arial,Helvetica,sans-serif;">A reaction with chlorine will give an alkyl chloride


 * || <span style="font-family: Arial,Helvetica,sans-serif;">light ||  ||
 * <span style="font-family: Arial,Helvetica,sans-serif;">CH4(g) +Cl2(g) || <span style="font-family: Arial,Helvetica,sans-serif;">→ || <span style="font-family: Arial,Helvetica,sans-serif;">CH3Cl(g) +HCl(g) ||

<span style="font-family: Arial,Helvetica,sans-serif;">Alkanes react with halogens in a so-called free radical halogenation reaction. The hydrogen atoms of the alkane are progressively replaced by halogen atoms. There are 3 steps in this:

<span style="font-family: Arial,Helvetica,sans-serif;">Initiation <span style="font-family: Arial,Helvetica,sans-serif;">-the halogen radicals form by homolysis. Usually, energy in the form of heat or light is required. <span style="font-family: Arial,Helvetica,sans-serif;">Chain reaction or Propagation <span style="font-family: Arial,Helvetica,sans-serif;">-the halogen radical abstracts a hydrogen from the alkane to give an alkyl radical. This reacts further. <span style="font-family: Arial,Helvetica,sans-serif;">Chain termination <span style="font-family: Arial,Helvetica,sans-serif;">-recombination of two free radicals.

= <span style="font-family: Arial,Helvetica,sans-serif; font-size: 260%;">ALKENES =

<span style="font-family: Arial,Helvetica,sans-serif;">﻿An alkene is made of carbons and hydrogens, but in the chain of carbons, there is one double bond. Since carbon has places for four bonds, it 2 of them are taken up in a double bond between 2 carbons. The formula for an alkene is **CnH2n**. They burn to form carbon soot and carbon dioxide and water. They are more reactive than alkanes because of the fact that they contain double bonds.


 * <span style="font-family: Arial,Helvetica,sans-serif;">Reactions: **

The alkenes are highly flammable and burn readily in air, forming carbon dioxide and water,. For example, ethene
 * 1. Combustion of Alkenes**

C2H4 + 3 O2 --> 2CO2 + 2 H2O

The alkenes are readily reduced by the addition of hydrogen across the double to form alkanes (i.e. reduction of alkenes). For example, when an alkenes is passed over a nickel catalyst at 150 degC, the alkene is reduced to an alkane.
 * 2. Hydrogenation of Alkenes**

H2C = CH2 + H2 --> CH3CH3, Ethene become Ethane

Ethene + Bromine + Water --> 2-bromotehanol
 * 3. Halogenation (producing a mono-substituted product)**



Ethene + Bromine --> 1,2-dibromoethane -The reaction with bromine happens at room temperature
 * 4. Halogenation (producing a disubstituted product)**

<span style="font-family: Arial,Helvetica,sans-serif;"> alcohols are produced from the direct hydration of alkenes.
 * <span style="font-family: Arial,Helvetica,sans-serif;">5. Hydration of Alkenes **

<span style="font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;"> 6. Polymerization of Alkenes <span style="font-family: Arial,Helvetica,sans-serif;">this is when alkene molecules combine with each other to make a large molecule which is called a polymer. The polymerization of alkenes are used to form products like plastic, ropes, food baskets, bowls and many others.

<span style="font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;">FUNCTIONAL GROUPS


 * <span style="font-family: Arial,Helvetica,sans-serif;">Alcohols **

<span style="font-family: Arial,Helvetica,sans-serif;"> Alcohols have relatively high boiling points because of hydrogen bonding <span style="font-family: Arial,Helvetica,sans-serif;">Soluble in water but decreases as parent chain gets bigger <span style="font-family: Arial,Helvetica,sans-serif;">Neutral, not an acid nor a base <span style="font-family: Arial,Helvetica,sans-serif;">Less volatile because of high boiling point

__<span style="font-family: Arial,Helvetica,sans-serif;">Reactions __

<span style="font-family: Arial,Helvetica,sans-serif;"> a. Combustion <span style="font-family: Arial,Helvetica,sans-serif;"> Like all other organic compounds, can be complete or incomplete <span style="font-family: Arial,Helvetica,sans-serif;"> Complete produces Carbon dioxide and water <span style="font-family: Arial,Helvetica,sans-serif;"> Incomplete produces carbon, carbon monoxide, carbon dioxide, water

b. Oxidation Oxidation - used to make aldehydes, ketones and carboxylic acids

Oxidizing agent- compound that gains electrons in an oxidation reaction

a.)Primary alcohol - can be oxidized to either aldehydes or carboxylic acids. - to form carboxylic acids, the alcohol is first oxidized to an aldehyde.

Partial oxidation - aldehyde is formed if you use an excess of alcohol and distill off the aldehyde as soon as it forms. - excess of alcohol means there isn't enough oxidizing agent. - if ethanol is used as a primary alcohol, aldehyde ethanal is produced.

Full oxidation - excess of oxidizing agent to make sure aldehyde is formed.- alcohol is heated with an excess of oxidizing agent - when reaction is complete, carboxylic acid is distilled off.

B.) secondary alcohol - oxidized to ketones only <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; line-height: 19px;">

C.) Tertiary alcohols - no reaction because tertiary alcohols don't have a hydrogen atom attached to the carbon.

<span style="font-family: Arial,Helvetica,sans-serif;">Low boiling points due to weak dipole-dipole bonds <span style="font-family: Arial,Helvetica,sans-serif;">Slightly soluble in water <span style="font-family: Arial,Helvetica,sans-serif;">No pH because it is a gas <span style="font-family: Arial,Helvetica,sans-serif;">Highly volatile
 * <span style="font-family: Arial,Helvetica,sans-serif;">Halogenoalkanes **

<span style="font-family: Arial,Helvetica,sans-serif;">Moderate boiling points due to moderate dipole-dipole bonds <span style="font-family: Arial,Helvetica,sans-serif;">Soluble in water but decreases as parent chain gets bigger <span style="font-family: Arial,Helvetica,sans-serif;">No pH <span style="font-family: Arial,Helvetica,sans-serif;">Moderately volatile
 * <span style="font-family: Arial,Helvetica,sans-serif;">Aldehydes **

<span style="font-family: Arial,Helvetica,sans-serif;">Moderate boiling points due to moderate dipole-dipole bonds <span style="font-family: Arial,Helvetica,sans-serif;">Soluble in water but decreases as parent chain gets bigger <span style="font-family: Arial,Helvetica,sans-serif;">No pH <span style="font-family: Arial,Helvetica,sans-serif;">Moderately volatile
 * <span style="font-family: Arial,Helvetica,sans-serif;">Ketones **

<span style="font-family: Arial,Helvetica,sans-serif;">High boiling points due to hydrogen bonding <span style="font-family: Arial,Helvetica,sans-serif;">Soluble in water <span style="font-family: Arial,Helvetica,sans-serif;">pH lower than 7 <span style="font-family: Arial,Helvetica,sans-serif;">Low volatility
 * <span style="font-family: Arial,Helvetica,sans-serif;">Caboxylic Acids **

<span style="font-family: Arial,Helvetica,sans-serif;">Hydrogen bond (primary and secondary); dipole-dipole (tertiary) <span style="font-family: Arial,Helvetica,sans-serif;">Soluble in water <span style="font-family: Arial,Helvetica,sans-serif;">no pH <span style="font-family: Arial,Helvetica,sans-serif;">Low volatility (primary and secondary); moderate volatility (tertiary)
 * <span style="font-family: Arial,Helvetica,sans-serif;">Amines **

<span style="font-family: Arial,Helvetica,sans-serif;"> Sources:

[| http://www.chemie.de/lexikon/e/Free_radical_halogenation/]
[] [] http://www.suite101.com/content/chemical-reactoins-of-alkenes-a250053 http://www.chemguide.co.uk/organicprops/alkenes/hydration.html#top http://www.chemguide.co.uk/organicprops/alkenes/halogenation.html http://www.chemguide.co.uk/organicprops/alkenes/polymerisation.html#top