Powerpoint outline on Alkanes for CSEC Chemistry.pptx

Powerpoint outline of Alkanes on CSEC Chemistry

1. Alkanes Alkanes are a group of hydrocarbons with the general formula of CnH2n+2. They are composed of only carbon and hydrogen atoms, and they are saturated hydrocarbons, which means that they have the maximum number of hydrogens in their molecules. Alkanes are also known as paraffins, which means that they are odorless and colorless.

2. Naming Alkanes Alkanes are named using the IUPAC system, meaning that they are named based on the number of carbons in the molecule. For example, methane is CH4 and has one carbon, while pentane is C5H12 and has five carbons. The suffix of the name changes with the number of carbons, from -ane for single carbon molecules to -eicosane for 20 carbon molecules.

3. Physical Properties Alkanes are non-polar molecules, so they are insoluble in water, but soluble in organic solvents. They are also gases at room temperature, except for longer molecules, which can be liquids or solids. Alkanes also have a low boiling point, meaning that they can easily be evaporated.

4. Reactivity Alkanes are generally unreactive, meaning that they do not spontaneously react with other molecules. They can, however, react with oxygen to form oxides, as well as with chlorine to form chlorinated compounds. They can also be broken down into smaller molecules through combustion.

5. Uses Alkanes are used in a variety of applications, including fuel for vehicles, lubricants, and solvents for degreasing. They can also be used as a starting material for the production of other chemicals, such as polymers and plastics.

6. Isomers Alkanes can have different isomers, which are molecules with the same formula but different structural arrangements. For example, butane can have two isomers, n-butane and isobutane, which have different physical and chemical properties.

7. Combustion Alkanes are highly flammable and can be easily combusted. When combusted, they produce carbon dioxide and water vapor, along with a small amount of soot. The amount of soot produced depends on the amount of oxygen available during the combustion process.

8. Halogenation Alkanes can be halogenated, meaning that they can react with halogen molecules, such as chlorine. This reaction results in the formation of alkyl halides, which are compounds that contain a halogen atom bonded to an sp3 carbon atom of an alkane.

9. Polymerization Alkanes can be polymerized, meaning that they can be broken down into smaller molecules, which can then be combined to form polymers. These polymers are used in a variety of applications, including insulation, packaging, and various plastics.

10. Addition Reactions Alkanes can react with other molecules in addition reactions, which result in the formation of new molecules. These reactions can be used to produce a variety of compounds, including alcohols, ethers, and aldehydes.

11. Substitution Reactions Alkanes can also react with other molecules in substitution reactions, which result in the replacement of one or more hydrogen atoms in an alkane molecule with other atoms. These reactions can be used to produce a variety of compounds, including halogenated compounds and reduced compounds.

12. Oxidation Reactions Alkanes can be oxidized, meaning that they can be broken down into smaller molecules. This can be done through a variety of methods, including combustion, catalytic oxidation, and hydrocarbon oxidation. Oxidation reactions are used to produce a variety of compounds, including alcohols, aldehydes, and carboxylic acids.

13. Catalytic Hydrogenation Alkanes can be hydrogenated, meaning that they can react with hydrogen molecules in the presence of a catalyst. This process is used to produce a variety of compounds, including alkenes, alkanes, and alcohols.

14. Reactions with Oxygen Alkanes can also react with oxygen to form oxides, which can be produced through combustion and catalytic oxidation. These reactions are used to produce a variety of compounds, including alcohols, aldehydes, and carboxylic acids.

15. Summary Alkanes are a group of hydrocarbons with the general formula of CnH2n+2. They are composed of only carbon and hydrogen atoms, and they are saturated hydrocarbons. Alkanes are non-polar molecules, and they are generally unreactive, except for with oxygen and chlorine. Alkanes can also be used to produce a variety of compounds, including alcohols, ethers, and aldehydes.