Presentation on theme: "QUOTE FOR THE DAY The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about."— Presentation transcript:
QUOTE FOR THE DAY The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it. Albert Einstein
CARBON IS A UNIQUE ELEMENT. IT IS IN THE CENTER OF THE PERIODIC TABLE AND HAS 4 VALENCE ELECTRONS. ITS ATTRACTION FOR ELECTRONS IS TOO GREAT FOR IT TO REACT BY LOSING ELECTRONS, BUT THE ATTRACTION IS NOT GREAT ENOUGH FOR IT TO REACT BY GAINING ELECTRONS. CARBON REACTS CHEMICALLY BY SHARING ELECTRONS - IT FORMS COVALENT BONDS.
CARBON CAN FORM FOUR SINGLE COVALENT BONDS WITH OTHER CARBON ATOMS OR WITH A NUMBER OF OTHER ELEMENTS. IN NATURE IT EXISTS IN THREE DIFFERENT FORMS. 1)GRAPHITE 2)DIAMOND 3)BUCKY BALLS THE FORM THAT IS STABLE AT LOW PRESSURES AND NORMAL TEMPERATURES IS GRAPHITE. DIAMOND IS STABLE AT HIGH PRESSURES AND TEMPERATURES.
DiamondGraphite Boiling Point 4827 C Melting Point 3550 C HardnessHardest sub. Known Soft ConductivityInsulatorGood conductor Density3.514 g/cm 3 2.26 g/cm 3
GRAPHITE CAN BE CONVERTED TO DIAMOND UNDER VERY HIGH PRESSURES AND TEMPERATURES. THIS CAN BE DONE IN THE LAB, AND INDUSTRIAL DIAMONDS ARE MADE THIS WAY. IN NATURE, IT IS THOUGHT THAT DIAMONDS WERE MADE DEEP UNDERGROUND IN THE VENTS OF VOLCANOES. DO DIAMONDS BURN??
Indeed, diamonds do burn. However, since they're pure carbon, and in the burning process are converted to carbon dioxide (only), there is no ash residue whatever. Had an interesting thing occur once when a home burned down and a rather "costly" jewelry piece was lost. It turned out that what was thought to be a diamond was found amid the melted gold remains of the setting. The stone was completely intact and undamaged. It was later discovered to be a cubic zirconia (fake diamond) that would not burn. The fellow's wife was not impressed that her husband would have fooled her into thinking he had spent big money on a diamond when he had actually bought her a vastly less expensive cubic zirconia. Regards, ProfHoff
SINCE CARBON CAN FORM CHEMICAL BONDS WITH ITSELF AND WITH A NUMBER OF OTHER ELEMENTS, LITERALLY MILLIONS OF CARBON CONTAINING COMPOUNDS EXIST. MANY OF THEM ARE IMPORTANT COMPOUNDS FOR LIFE. INDEED, CARBON CONTAINING COMPOUNDS ARE THE BASIS FOR LIFE AS WE KNOW IT.
Major ElementsSymbol Percentage (by weight) OxygenO65.0 CarbonC18.5 HydrogenH9.5 NitrogenN3.3 CalciumCa1.5 PhosphorusP1.0 PotassiumK0.4 SulfurS0.3 SodiumNa0.2 ChlorineCl0.2 MagnesiumMg0.1 Trace Elements together less than 0.1% boron (B), chromium (Cr), cobalt (Co), copper (Cu), Fluorine (F), iodine (I), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), silicon (Si), tin(Sn), vanadium(V), & zinc(Zn).
IF YOU CONSIDER JUST THE COMPOUNDS FORMED BETWEEN CARBON AND HYDROGEN, THERE ARE MILLIONS OF COMPOUNDS IN EXISTENCE. MANY OF THESE ARE IMPORTANT AS FUELS. COMPOUNDS FORMED FROM CARBON AND HYDROGEN ARE CALLED HYDROCARBONS. THE SIMPLEST HYDROCARBON IS METHANE, A MAJOR COMPONENT IN NATURAL GAS.
THE NEXT HYDROCARBON IN THE SERIES IS ETHANE, ALSO FOUND IN NATURAL GAS.
AS YOU CONTINUE TO ADD CARBONS, YOU GET ADDITIONAL COMPOUNDS.
WITH BUTANE (4 CARBONS), THERE TURNS OUT TO BE MORE THAN ONE WAY TO ARRANGE THE CARBONS IN THE MOLECULE. THESE COMPOUNDS HAVE THE SAME GENERAL FORMULA, C 4 H 10 THEY ARE CALLED ISOMERS.
ISOMERS ARE COMPOUNDS WITH THE SAME GENERAL FORMULA, BUT DIFFERENT STRUCTURAL FORMULA. AS THE NUMBER OF CARBONS INCREASES, THE NUMBER OF POSSIBLE ISOMERS INCREASES. No. of CarbonsNo. of Isomers 65 79 935 1075 20366,319 304,111,846,763
YOU WOULD FIND MANY OF THESE COMPOUNDS IN PETROLEUM. THIS MAKES PETROLEUM A VERY COMPLEX MIXTURE, AND SOME OF THE COMPOUNDS HAVE PROPERTIES THAT ARE IMPORTANT TO CERTAIN KINDS OF FUELS. ONE OF THE PROCESSES PETROLEUM UNDERGOES IS DISTILLATION. DISTILLATION IS SEPARATION OF THE COMPOUNDS BY BOILING POINT. THIS ALSO SEPARATES THE COMPOUNDS BY NUMBERS OF CARBONS PER MOLECULE.
FOR EXAMPLE: NATURAL GASC1 AND C2 COMPOUNDS LPGC3 AND C4 GASOLINEC5 TO C12 KEROSINEC12 TO C18 DIESEL FUELC14 TO C20 HOME HEATING OILC16 TO C22 LUBRICANT BASE OILC20 TO C40