Organic Chemistry - Hydrocarbon

Organic chemistry

is the study of carbon compounds

Hydrocarbons

are compounds that contain carbon and hydrogen only

Fossil fuels

are fuels that were formed from the remains of dead plants and animals that lived millions of years ago

How is fossil fuels a source of hydrocarbon

Crude oil is a mixture of hydrocarbons that’s separated into fractions, based on boiling range, by fractional distillation

Biomass

is any organic material derived from plants or animals. It can act as a renewable feedstock for producing fuels and other organic compounds

The sources of biomass for hydrocarbon

1. Anaerobic digestion: Microorganisms are used to break down the organic matter in the absence of oxygen. This results in the production of methane-rich biogas

2. Pyrolysis: This involves using heat to break down organic matter in the absence of oxygen. This can produce gases, liquids (bio-oil) and solid char

Homologous

a series of compounds with similar chemical properties, have the same general formula, show a gradual change in physical properties, and contain the same functional group.

Saturated compound

is a compound in which there are only single bonds between its atom

Properties of Alkanes

1. Soluble in non-polar solvent e.g. cyclohexane

2. Insoluble in water because the alkanes are non-polar - they only have London dispersion forces between the molecules

3. C₁-C₄ are gases. C₅-C₁₆ are liquids, C₁₇ and above are waxy solids - this is because the larger molecules have stronger London dispersion forces, increasing their boiling and melting points

4. Straight-chain isomers have stronger London dispersion forces than more highly branched isomers (therefore, straight-chain isomers have a higher boiling point)

What’s the formula for Alkanes

C_n H_2n+2

Structural isomers

are the compounds that have the same molecular formula but different strucrtual formula

What the sub word for fluorine

fluoro

What the sub word for chlorine

chloro

What the sub word for bromine

bromo

What the sub word for iodine

iodo

What does cyclo

hydrocarbon’s longest chain of carbon atoms form a ring

Unsaturated

is a compound which contains one or more double or triple bonds between its atoms

What’s the formula for Alkenes

C_nH_2n

Properties Alkenes

• Soluble in non-polar solvent e.g. cyclohexane

• Insoluble in water because the alkenes are non-polar - they only have London dispersion forces between the molecules

• The lower alkenes (C₂-C₄) are gases at room temperature; intermediate members are liquids and higher members are solids. As molecular size increases, stronger London dispersion forces raise boiling and melting points

Stereoisomer

an unsaturated hydrocarbon there’s restricted rotation about the carbon-carbon double bond giving rise to a different type of geometrical isomer

Geometric isomer

are molecules with the same structural formula but different arrangements of atoms in space