The Chemistry of Carbon

Chemistry in the Marketplace

Chemistry is the science of matter. It deals with the composition of substances and their properties and reactions.Marketplace is a site where goods are sold.

Goods in the marketplace usually contain organic compounds.

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How Carbon compounds are formed. Allotropes of carbon Covalent bonding

Fossil Fuels How fossil fuels are formed? Uses of fossil fuels. Distillation Fractional distillation cracking

Hydrocarbons Alkanes Alkenes Alkynes Ringed Hydrocarbons Functional Groups

Cosmetics DdPlastics dd

Chemical Bonding

Metallic Bonding – forces of attraction between positive metal ions and free electrons between them.

Ionic Bonding – when atoms or groups of atoms lose and gain electrons

Covalent Bonding – when atoms share electrons

How carbon forms compounds

Organic compounds are compounds consisting of Carbon

Compounds – is a pure substance that contains two or more elements chemically bonded together in fixed portions.

Molecular Compounds – are when 2 or more atoms are covalently bonded together.

Where can Carbon compounds be found

What do graphite and diamond have in common?

Allotropes of Carbon

The element Carbon has two common allotropes: diamond and graphite. This means that they are both made of only Carbon.

Diamond has Carbon atoms bonded in a tetrahedral lattice arrangement

Graphite has Carbon atoms are bonded together in sheets of hexagonal lattice.

Covalent Bonding

Compounds that are formed by sharing of electrons

Happens between non-metals

ExamplesHCl Cl2 CH4

Covalent bonding

When 2 non-metallic atoms bind together, eg H atom and H atom to make molecules in the element Hydrogen, both atoms need to gain electrons in order to achieve a complete outershell. They achieve this complete outershell by sharing pairs of electrons and this is called a covalent bond.

A covalent bond is the electrostatic attraction between the negatively charged shared pair of electrons and the positive nucleus of each atom. The electrostatic attraction holds the atoms together and forms the molecule.

Covalent bonding occurs only between non-metal atoms and results in molecules.

Covalent bonding….

In the case of covalent compounds containing carbon, each carbon atom has 4 valence (outer shell) electrons and needs 4 more electrons to achieve a full outer shell. Therefore carbon atoms in compounds always share their 4 valence electrons and always have 4 bonds.

Procedures for writing out organic covalent substances

STEP 1 Write out a formula CH4

STEP 2 List all the elements and their electronic configuration.Circle the last shell.Write out how many electrons each needs to make a full outer shell.

C 2, 4 needs 4 electronH 1 needs 1 electronH 1 needs 1 electronH 1 needs 1 electronH 1 needs 1 electron

STEP 3 The element that needs the most electrons to share is the central element.

Carbon is the central element

STEP 4 Draw the structure. Electron dot Lewis diagram

Structural Formula

Procedures for writing out organic covalent substances

STEP 1 Write out a formula Cl2

STEP 2 List all the elements and their electronic configuration.Circle the last shell.Write out how many electrons each needs to make a full outer shell.

Cl 2, 8. 7 needs 1 electronCl 2, 8. 7 needs 1 electron

STEP 3 The element that needs the most electrons to share is the central element.

STEP 4 Draw the structure. Electron dot Lewis Diagram

Structural Formula

Procedures for writing out organic covalent substances

STEP 1 Write out a formula HCl

STEP 2 List all the elements and their electronic configuration.Circle the last shell.Write out how many electrons each needs to make a full outer shell.

Cl 2, 8. 7 needs 1 electronH 1 needs 1 electron

STEP 3 The element that needs the most electrons to share is the central element.

STEP 4 Draw the structure. Electron dot Lewis Diagram

Structural Formula

Fossil Fuels

▪ Coal

▪ Crude Oil

▪ Natural Gas

Organic Chemistry is the chemistry of life. Nearly all organic compounds have come from plants or animals that were once living. Fossil Fuels such as coal, natural gas, and crude oil were derived from plants and animals that died million of years ago and become buried under sediments. Pressure and time enabled the formation of these organic compounds.Fossil fuels can be extra:

Non renewable forms of energy Fossil fuels are made naturally from

decaying plants and animals living millions of years ago. Coal was made from plant material. Most of

the coal was formed in the Palaeozoic Era in the Carboniferous Period.

Crude oil is unprocessed oil that comes out of the ground. This was formed in ancient sea beds.

Natural gas consists mainly of methane. It can be associated with fossil fuels.

Uses of Fossil Fuels

▪ Fuels▪ Plastics▪ Synthetic textiles▪ Lubricants▪ Waxes▪ Pharmaceuticals▪ Cosmetics▪ Fragrances▪ Artificial flavourings▪ Paints▪ Solvents▪ Pesticides▪ Explosives

From these basic compounds, chemical industries can produce;

ACTIVITY

Uses of Crude Oilhttp://carbonchemistry.wikispaces.com/Fossil+Fuels

Distillation

is the process used to separate substances that have different boiling points. This process is used to make perfumes by extracting oils (which have much lower boiling points and therefore easily evaporate) from plants and flowers.

It involves evaporation and allows you to collect the substance boiled off as well as the substance with a much higher boiling point left in the flask (solute).

The substance boiled off is condensed(turned back into a liquid) by being cooled in a condenser.

http://www.youtube.com/watch?v=mAyAoLb8_xQ

Fractional Distillation

Is the process used to separate a mixture of liquids using different boiling points.

The mixture is boiled and the vapours pass up the fractionating column.

The substances with a higher boiling point are collected higher up the column where the temperatures are lower.

Cracking

Cracking takes large hydrocarbons and breaks it up into smaller hydrocarbons.

Thermal cracking uses high temperatures to break apart the hydrocarbons.

Catalytic cracking uses a catalyst (e.g. zeolite aluminium hydrosilicate, bauxite and silica-alumina)to speed up the cracking reaction

http://science.howstuffworks.com/oil-refining5.htm

Although petrol is in heavy demand, it is only about 12% of crude oil. To increase the proportion of the lighter more useful fractions, the larger molecules are cracked into smaller molecules.

Hydrocarbons

Carbon can form long chains of carbon atoms.

Hydrocarbons are organic compounds that contain the elements carbon and hydrogen only.

These can form 3 different series called alkanes, alkenes and alkynes

Alkane series

The simplest group of hydrocarbons which contain only single bonds. The general formula for an alkane is CnH2n+2

The names of alkanes end in ane.

Alkene series

Alkenes are hydrocarbons with a carbon-carbon double bond. The general formula for an alkene is CnH2n

The names of alkenes end in ene.

Alkyne series

Alkynes are hydrocarbons with a carbon-carbon triple bond. The general formula for an alkyne is CnH2n-2

The names of alkynes end in yne.

Ringed hydrocarbons

Cyclo-alkanes – Alkanes can form rings by losing 2 hydrogen atoms

HexaneC6H14

Cyclohexane + Hydrogen C6H12 + H2

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Ringed hydrocarbons

Aromatic hydrocarbons – example Benzene Benzene consists of a carbon ring of 6 carbons each bonded to a

hydrogen atom. 6 remaining valence electrons form a ring of delocalised electrons

Aromatic hydrocarbons – example Napthalene Napthalene consists of 2 benzene rings joined together It is used to repel moths

Functional Groups

Is a group of atoms that gives a characteristic set of properties to a molecule containing that group.

Functional Group Name

Functional Group Symbol

Chloro -Cl

Hydoxyl -OH

Amino -NH2

Carboxyl -COOH

Methyl -CH3

Ethyl -CH2CH3

Cosmetics

Lip balm

Bath bombs

Hand Cream

Scents

Lip Balm

Answer the following questions:1. Describe the purpose of lip balm2. Explain why bees wax is so desirable for

making candles3. Describe where paraffin wax comes from4. Name two elements that make up

paraffin wax.5. Explain how petroleum jelly, bees wax

and paraffin wax are connected with each other.

Chemistry in bath bombs

Go over handout - Chemistry in Bath bombs

Two phases were produced when making hand cream:

▪Oil phase

▪Water phase

OIL PHASE this consisted of Lanolin and Stearic AcidLanolin

▪ Is a waste product in wool processing.▪ Is a greasy, yellow substance extracted from wool known as wool

wax, wool fat or wool grease.▪ It is used as a base for ointments and creams, as a lubricant and in

preserving leather.▪ Lanolin is mainly a mixture of organic compounds known as fatty

acid esters of cholesterol, lanosterol and fatty alcohols.

Stearic Acid▪ Is a saturated fatty acid that’s mainly in animal products▪ It is also in some plant foods like chocolate▪ Is is an example of a fatty acid.

Chemistry in hand cream

Fatty acids are long molecules consisting of a carbon and hydrogen chain with a carboxylic acid group (-COOH) at the end. The long tail of the molecule, made up of carbon and hydrogen, is not attracted to water and is said to be hydrophobic (water-fearing). The carboxylic acid “head” can form hydrogen bonds with water, and is therefore strongly attracted to water. It is said to be hydrophilic (water loving).

Hydrophilic head(carboxylic acid)

Hydrophobic tail (hydrocarbon chain)

WATER PHASE This consisted of Triethanolamine, Glycerol

and water.Triethanolamine

▪ Is used as a pH balancer in a variety of different Products ranging from skin lotion, eye gels, moisturizers, shampoos, shaving foams….

Glycerol▪ Is a 1,2,3 trihydroxy propane, a trihydric alcohol.▪ Also known as glycerine and glycerin.▪ Can be used as a sweetener.

Water▪ a compound of hrdrogen and oxygen.

Polymer

comes from the Greek words poly(many) and meros (parts).

is a molecule made up of thousands of units strung together in very long chains.

These single units are known as monomers.

PLASTICS or synthetic Polymers

Properties of Plastics

They are light, which means they are useful when the weight of an object has to be considered.

They can be made very hard or very soft, and therefore can be adapted to suit a particular need.

They are non-conductors of electricity, which makes them important in the manufacture of electrical goods.

They are able to be moulded in an infinite variety of shapes.

They can be used as extremely thin sheets or thick blocks.

They are non-rusting, and therefore theoretically have a longer life than metals and can be exposed to weather.

They come in multitude of colours, so painting is not necessary.

They are relatively cheap to manufacture.

They do not shatter, which in some cases makes them safer than glass.

They are generally good heat Insulators:this makes them appropriate for kitchenware, and able to be washed in hot water.

They resist microbe attack and therefore make good containers in which to store food.

Properties of Plastics cont…

PLASTICS or synthetic Polymers

Are polymers classified by their thermal behaviour.

Thermoplastic Polymers can be repeatedly melted and reshaped and then hardened by cooling they have low melting points they can be flexible because chains easily slide past each other

because of weak forces between the chains

Thermosetting plastics

Are polymers which do not melt but char when heated They are very hard and rigid (chains cannot slip past each

other) The greater the number of cross-links the more rigid the

polymer when sufficient heat is supplied the covalent bonds break and the polymer decomposes i.e. leaving a carbon residue.

Polymerisation

Polymerisation reactions occur when monomers are linked together to form a polymer (i.e. large molecules)/

There are two types of polymerisation reactions

AdditionCondensation

Addition polymerisation

One way of making a polymer is to begin with a monomer molecule which contains a double bond between two carbons. This double bond breaks to allow long chains to form.

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CATALYST

PolyetheneetheneEthene (obtained from cracking crude oil)

-on average there are 15,000 carbon atoms on each polymer chain

Condensation polymerisation

Another way of making a polymer is to begin with two different monomers molecules .

The monomers are able to react at both ends

a molecule of water is also formed as a result of the reaction.

Nylon can be made in this way.

Glossary

Catalyst Isomer