Composition and properties of diamondComposition Diamond is one of several allotropes of carbon, with the principle allotrope being graphite.Diamonds are formed when carbon deposits are exposed to high pressure and high temperature for prolonged periods of time. Diamonds have a characteristic crystalline structure, and therefore, a predictable crystal growth pattern known as its "crystal habit." This means that diamond crystals usually "grow" in an orderly and symmetrical arrangement. The natural crystal form, and crystal habit of a diamond is octahedral , although in nature, perfectly formed crystals are rareProperties 1. Diamond is the hardest known natural material on Earth.2. Diamond conducts heat 5 times faster than copper, which is why it feels cold to the touch.3. Pure diamond is the most transparent material known. It reects !isi"le li#ht, ultra$!iolet li#ht, and infrared li#ht, and all the fre%uencies in "etween.&. Diamond can "e an insulator or a conductor, so it can either allow electricity to pass throu#h or "lock it.5. Diamond can sur!i!e intact in en!ironments that will destroy other materials. It can sur!i!e se!ere physical, chemical and radioacti!e forces.Examples of Hydrocarbons and their use.1. Plastics $ 'any of the plastics we use in e!eryday life and in industry are made from lon# chains of monomers, formed from petrochemicals. (hese petrochemicals are simply hydrocar"ons of di)erent chemical compositions.2 Para*n $ (he wa+ that we use for a !ariety of industries, e!erythin# from candle makin# and food preser!ation to medical and industrial uses, contains hydrocar"ons.3. Isopropyl alcohol $ (his common medical chemical is interestin# in that it containsa hydrocar"on that is then "onded to further car"on atoms. &. ,sphalt $ the common su"stance that most people are familiar with is actually a hydrocar"on that has "een heated to form the su"stance tar. It is then mi+ed with other key industrial in#redients to form the mi+ture that makes up the road-s surface.5. Pentane is a clear li%uid at room temperature, commonly used in chemistry and industry as a powerful nearly odorless sol!ent of wa+es and hi#h molecular wei#ht or#anic compounds, includin# #reases... Propane is easily li%ue/ed, and e+ists in -propane "ottles- mostly as a li%uid, usedmostly in porta"le #as sti!e. 0. 1utaneis easily li%ue/ed that it pro!ides a safe, !olatile fuel for small pocket li#hters. 2. 3e+ane $ are si#ni/cant constituents of #asoline. (hey are all colorless li%uids at room temperature, odorless when pure.4. 5aphthalene is an aromatic hydrocar"on . Its most common and familiar use is in moth"alls.16. (rinitrotoluene 7(5(8 is one of the many deri!ati!es of the aromatic hydrocar"ons . Its formal name is 2,&,.$trinitrotoluene. It is used widely as an e+plosi!e and as a comparison for the e+plosi!e power of other e+plosi!es.