Chapter 14 Group 14 Elements Occurrence, extraction and uses Physical Properties Elements Hydrides, halides, carbides, hydroxides, oxoacids Silicones Sulfides 1 Relative abundances of the group 14 elements in the Earth’s crust. • Data are on a logarithmic scan and units of abundance are ppm. Occurrence Extraction Uses http://www.abrasivediamond.com/ 2 Uses of natural graphite in the US in 2009. http://en.wikipedia.org/wiki/File:Activated_Carbon.jpg http://www.koenigsegg.com/models/ccxr/ The declining use of leaded fuels in motor vehicles. 3 Physical properties of the group 14 elements, M, and their ions. Physical properties of the group 14 elements, M, and their ions. 4 Experimental covalent bond enthalpy terms (kJ mol1) C-C bonds are strong Si-Si double bond Si-Si triple bond mes = 5 -graphite proposed structure of CFn for n = 1 Allotropes element's atoms are bonded together in a different manner 6 Structure of the fullerene C60; the approximately spherical molecule is composed of fused 5- and 6-membered rings of carbon atoms. Structure of C70 7 Halogenation reactions of C60 C60Br24 C60F18 C60Cl30 8 + structure of C62(C6H4-4-Me)2 K3C60 and Rb3C60 9 tetraidecahedral dodecahedral share a pentagonal face Methane hydrates Boiling points of the straight-chain silanes, SinH2n2, and hydrocarbons CnH2n2. Synthesis: 10 Representative reactions of SiH3Cl [Sn ]4- 9 3- [Ge9] Zintl ions Example preparation Na in liquid NH3 2,2,2-crypt in Sn NaSn1.0-1.7 1,2-ethanediamine [Na(crypt-222)]2[Sn5] 11 6 arachno-[Sn8] Rb4Li2Sn8 6 [(Ge9)2] 12 [Sn12] Wade’s Rules 6- [(Ge9)3] 12 2 4 [Pt@Pb12] [Pd2@Ge18] Stabilization of large cage Zintl phases with an interstitial atom. Selected physical properties of the carbon and silicon tetrahalides. Propose a method to dry halogenated solvents (e.g. CCl4) 13 CFCs 2 [SiF6] [SiF5] 2 trans-[SiCl2(MeIm)4] 14 Halides of tin [SnCl2F] [Sn2F5] 4 6 [Pb3I10] [Pb5I16] 15 Selected properties of CO and CO2 Selected low-temperature baths involving dry ice.† 16 Transition temperatures between polymorphs of SiO2 Ionic radii of selected ions involved in silicates 17 Silicates 8 12 [Si8O20] [Si12O30] 18 Part of one of the double chains of general formula 6n [Si4O11]n present in the mineral tremolite H-ZSM-5 zeolite is typical of a zeolite in possessing cavities which can accommodate guest molecules. 19 Two views (a) from the side and (b) from above of a part of one layer of the SnO and red PbO lattices. Colour code: Sn, Pb, brown; O, red. • Part of the network structure of Pb3O4 (i.e. 2PbO PbO2) showing the (IV) interconnected chains of octahedral {Pb O6}-units and trigonal pyramidal (II) {Pb O3}-units. Colour code: Pb, brown; O, red. 20 Selected properties of ES2 (E = C, Si, Ge, Sn). 21.