Organic Compounds An organic compound is any compound that contains both Carbon (C) and Hydrogen (H) in its chemical formula. Carbon is an atom that is exceptional at making many compounds because it can make 4 covalent bonds.
Hydrocarbons Hydrocarbons are the simplest organic compounds. Hydrocarbons are organic compounds ONLY made of Hydrogen and Carbon.
Saturated and Unsaturated Hydrocarbons. In a saturated hydrocarbon, all carbon atoms form single bonds with hydrogen. They are saturated because they make the maximum number of hydrogen bonds. (Ex: C2H6) Unsaturated hydrocarbons make at least one double or triple covalent bond in the molecule (Ex: C2H2)
Common Hydrocarbons Methane (Natural Gas) Butane (Found in lighters) Propane (Outdoor Gas Grills) Octane (Found in Gasoline) Ethylene (Found in Crude Oil and Plastics)
Basic Organic Compounds
Isomers A molecule that has the same chemical formula as another molecule (meaning the same #of atoms) is known as an isomer. Two isomers are different because the atoms are not arranged in the same way. Isomers will have slightly difference properties (chemical and physical) because of the different arrangements of the molecules.
Graphite vs. Diamond
Aromatic Hydrocarbons The chemical bonds in aromatics form a ring in the structure made of at least 6 carbon atoms in the molecule. Aromatics have a strong smell to humans, some pleasant and others foul. The most common aromatic hydrocarbon is benzene (C6H6), which is found in gasoline. Benzene is a known carcinogen in humans.
Other Organic Compounds (Aromatics)
Other Organic Compounds Substituted Hydrocarbons: Another elements is substituted in the molecule for hydrogen, such as chlorine (Cl) or sulfur (S). (OH) ions make alcohols. (COOH) groups make organic acids
Polymers Definition: A molecule that is made of repeating structural units. Each individual unit is known as a monomer.
Examples of Polymers Plastics (synthetic) Rubber (synthetic and natural) Cellulose (natural) DNA (natural) Protein (natural)
Important Vocabulary Plastic – Bendable, but does not return to original shape -- Plastomer – bendable polymers Elastic – Bendable, but does return to original shape -- Elastomers – Elastic polymers Brittle – Not flexible. Will break, not bend
Linear Polymer Structure Polymers that are bonded in straight lines Generally high Melting Point High Density
Branched Structure Monomers branch off a polymer structure Low Density because they occupy more space
Entanglement When polymer chain (or chains) get tangled Think of a tangled ball of string Cold pile of spaghetti More entangled = stronger and less flexible
Cross-Linked Polymer Linear polymers are linked together Hard, brittle, not flexible More cross-links = increase strength and stiffness
Addition of Heat Chains tangle Chains untangle Think of shrink wrapping on DVD’s Polymer shrinks as chains tangle Chains untangle Think of stretching some hot plastics Polymers are able to be stretched and untangled
Molecular Structures of Polymers Used for Plastics The ethylene molecule is manipulated in different chain structures to give the plastic certain physical properties. The base hydrocarbon is substituted with other atoms (ex, chlorine in PVC) to create new plastics with different physical properties.
Petroleum Petroleum is the natural resource that is used to make several common polymers, including plastics. Petroleum is a dark black liquid that is a mixture of organic compounds. Petroleum forms from the remains of ancient plant life in shallow oceans. (NOT DINOSAURS!)
Oil Refineries
Boiling points When the temperature reaches the boiling point, the average kinetic energy of the liquid particles is sufficient to overcome the forces of attraction that hold molecules in the liquid state. Then these molecules break away from the liquid forming the gas state
Combustion of fossil fuels Incomplete: 2C3H8 + 7O2 6CO + 8H2O Complete C3H8 + 5O2 3CO2 + 4H2O
Incomplete Combustion Incomplete combustion forms CO and forms when there is insufficient oxygen to form CO2 It is a problem b/c it bonds to hemoglobin better than CO2, ruins the hemoglbin cell and can suffocate you! Excess carbon particles cause respiratory distress!
Common Household Items Made of Plastic
Top Oil Consuming Countries of the World
Tensile Strength – The amount of force that can exerted on a material before it fails. PVC Polyvinylchloride PS Polystyrene HDPE High density polyethylene PP Polypropylene
Melting Point PVC Polyvinylchloride PS Polystyrene HDPE High density polyethylene PP Polypropylene