Carbon Chemistry

9.5 Content Standard D 13. Explain how the structure of the carbon atom affects the type of bonds it forms in organic and inorganic molecules.

What’s so special about Carbon? Fourth most abundant element in the universe. Essential to life on earth. Many different forms… carbon dioxide (CO2), limestone (CaCO3), wood, plastic, diamonds, and graphite.

Carbon – The Element of Life Unique atomic structure… form covalent bonds with up to four other atoms. Elements with either less or more than 4 valence electrons can only form a maximum of 3 covalent bonds, this is why 4 is a magic number and why carbon is special. Lightest element (and therefore the smallest) with four valence electrons

Carbon Structures Chains Rings Branches

Carbon Bonds Single Double Triple

Carbon Recall How many valence electrons does carbon have? What 3 types of structures does carbon form? Rings, Chains, and Branches

Inorganic Compounds Inorganic compounds are those compounds that were never part of a living organism Examples: Carbon dioxide and Carbon monoxide The line between inorganic and organic carbon compounds is becoming less and less important to scientists as many non-living compounds are derived from once living organisms.

Organic Compounds Organic compounds are those compounds found in any organism that is living or was once living. Chemically… Organic compound – any compound that contains the elements carbon and hydrogen. They include carbohydrates such as glucose, fructose, and sucrose And hydrocarbons such as methane and hexane

Carbon Recall What is the difference between organic & inorganic compounds? Give an example of an organic compound. Give an example of an inorganic compound.

Carbohydrates (Organic) Monosaccharides- One unit (Simple Sugar) Disaccharides- Two units (Simple Sugar) Glucose- stored in our body Fructose- sugar in fruit Sucrose- one glucose + one fructose = table sugar

Carbohydrates (Organic) Polysaccharides- Many units (Complex Carbs) Starch- a long chain of glucose- found in plants Similarly, Glycogen is glucose stored in animals and humans. Cellulose is glucose chains linked together and forms strong plant fibers.

Hydrocarbons (Organic) Pure hydrocarbons- only Carbon + Hydrogen Isomers of Octane- often added to gasoline to stop the “knock” in the engine

Isomers Isomers- “Iso” means equal “mers” parts Definition: Molecules with the same chemical formula but different chemical structures. http://en.wikipedia.org/wiki/Isomer

Isomers

Saturated vs Unsaturated Saturated hydrocarbons have the maximum amount of hydrogens possible. Hydrocarbons with all single bonds are considered to be saturated. Alkanes Unsaturated hydrocarbons do not have the maximum amount of hydrogens possible. Any hydrocarbon with double or triple bonds are unsaturated. Alkenes and Alkynes

Saturated vs Unsaturated

Prefix # Carbons Name Formula Structure Meth 1 Methane CH4 Eth 2 Ethane C2H6 Prop 3 Propane C3H8 But 4 Butane C4H10 Pent 5 Pentane C5H12 Hex 6 Hexane C6H14 Hept 7 Heptane C7H16 Oct 8 Octane C8H18 Non 9 Nonane C9H20

Properties of Hydrocarbons Hydrocarbons are the simplest organic compounds, made up of only two elements -- they have low melting and boiling points -- hydrocarbons are flammable and tend to burn in combustion reactions -- hydrocarbons mix poorly with water (they are nonpolar) -- hydrocarbons are used for many of our fuels such as heating oil, diesel fuel, gasoline, coal and methane.

Carbon Recall Name two examples of organic molecules. Carbohydrates & Hydrocarbons Name one characteristic of hydrocarbons. Do not dissolve in water

The Carbon Cycle Elements such as Carbon exist in fixed (limited) amounts on the earth and are located in various chemical pools called reservoirs. The movement of carbon, in its many forms, between the atmosphere, oceans, biosphere, and solid earth is described by the carbon cycle. This cycle is driven by both the Earth’s internal (geothermal) energy, and the external energy from the sun and can be divided into geological, chemical and biological components.

The global carbon cycle Sources and sinks of carbon will add or remove carbon from the active part of the cycle. Carbon sinks include long-lived trees, limestone (formed from shells of small sea creatures that settle to the ocean bottoms, plastic, and the burial of organic matter (form fossil fuels). Carbon sources include the burning of fossil fuels and other organic matter, the weathering of limestone rocks (CO2 released), volcanic activity, forest destruction, and the respiration of living organisms. Reservoirs (in black) are gigatons (1Gt = 1x109 Tons) of carbon, and fluxes (in purple) are Gt carbon per year.

Carbon Recall Where is carbon located within the carbon cycle? Name one source of carbon. Carbon Reservoirs, Burning of fossil fuels