Andrea Pazourková Petra Doušová Presentation to the technical English Theme: CARBON

Physical propetries of carbon: Physical propetries of carbon:  Atomic Number: 6  Atomic Mass Average:  Melting Point: 3823 K (3550°C or 6422°F  Boiling Point: 4098 K (3825°C or 6917°F)  Stable Isomers (2)  There isotopes ( carbon 12,13 and 14 )

Atomic structure: Carbon has six electrons, 4 of the electrons are in its valence shell (outershell). The circles in the diagram show energy levels - representing increasing distances from the nucleus. The picture gives us the impression that the electrons are circling the nucleus in orbits like planets around the sun.

Here we see carbon has six electrons represented by arrows. Two electrons are found in the 1s orbital close to the nucleus. The next two will go into the 2s orbital. The remaining two will be in two separate 2p orbitals. This is because the p orbitals have the same energy and the electrons would rather be in separate orbitals. Energy level graph: - a better way to look at carbon is by using an

2s 2px 2py

Isotopes: Isotopes are atoms which have the same atomic number but different mass numbers. They have the same number of protons but different numbers of neutrons. There are three kinds of carbon atom 12C, 13C and 14C. They all have the same number of protons, but the Number of neutrons varies. protonsneutrons mass number carbon carbon carbon

Elemental Carbon: Carbon is found in many different compounds. Carbon and its components are widely distributed in nature. It is in the food you eat, the clothes you wear, the cosmetics you use and the gasoline that fuels your car. Carbon is the sixth most abundant element in the universe. In addition, carbon is a very special element because it plays a dominant role in the chemistry of life. There are four known allotopes of cabon: Carbon is found in many different compounds. Carbon and its components are widely distributed in nature. It is in the food you eat, the clothes you wear, the cosmetics you use and the gasoline that fuels your car. Carbon is the sixth most abundant element in the universe. In addition, carbon is a very special element because it plays a dominant role in the chemistry of life. There are four known allotopes of cabon:  amorphous - is used as gas absorbent and bleaching agent agent  graphite  diamond  fullerene

1)Graphite – is probably best known for its use in pencil 'lead', also is used for high temperature crucibles, dry cell and light arch electrodes 2) Diamond - is the hardest substance known to man, it has a dense, extremely stable crystalline structure, it is good conductor of heat and electricity

Compounds of carbon: 1) carbon+hydrogen Organic compounds - we know a minimum of about 1 million Organic compounds - we know a minimum of about 1 million methane ethanol benzene 2) carbon + oxygen carbon monoxide CO and carbon dioxide CO 2 – are the most important from the industrial point of view, CO is used as reducing agent, CO 2 is used in drinks carbonatation or in fire extinguishers.

3) Carbon + halogens general formula is CX 4 - where X is fluorine, chlorine, bromine or iodine  (C 2 F 4 ) n – teflon – is used or pots, pans, ….  CCl 2 F 2 – freon – used in refridgerators  CCl 4 – carbon tetrachloride, CHCl 3 – chloroform, C 2 H 2 Cl 2 – dichloroethylene – are used to make a solvents 4) Minerals - like limestone, dolomite, gypsum and marble, contain carbonates 5) Calcium carbide - is used to prepare acetylene, for welding and cutting metals, as well as for preparation of other organic compounds

The End Thank you for your attention