Transcript petrucci12b
Kovalent Bağlar •Kovalent Bağ nedir? - Kovalent bağ, bağ yapan iki atom arasında elektronların paylaşılması sonucunda oluşan kimyasal bir bağdır. • Bir kovalent bağ nasıl oluşur? - Bir kovalent bağ iki ametal arasında oluşur. Kovalent Bağ: Elektronlar ortaklaşa kullanılır. Oksijen Molekülü(O2) H H C H methane, CH4 H 109.5° less repulsion between the bonding pairs of electrons 90° Are there atomic orbitals on C, Si, N and O to accommodate the bonding electrons of the shapes predicted by VSEPR? 3 p orbitals s orbital x y x y z z Are there atomic orbitals on C, Si, N and O to accommodate the bonding electrons of the shapes predicted by VSEPR? x y x y z z Are there atomic orbitals on C, Si, N and O to accommodate the bonding electrons of the shapes predicted by VSEPR? 4 sp3 orbitals x y z Are there atomic orbitals on C, Si, N and O to H accommodate the bonding electrons of the shapes predicted by VSEPR? 4 sp3 orbitals x y C H z H H Methane building blocks 1s 2s 2px 2py 2pz Promotey sp3 sp3 sp3 sp3 Hybridize x 109.5o z Methane: Carbon SİGMA (d) BAĞ OLUŞUMU hybrid orbitals – sp, sp2, or sp3 formation of s bond Figure 11.9 The s bonds in ethane. both C are sp3 hybridized s-sp3 overlaps to s bonds sp3-sp3 overlap to form a s bond relatively even distribution of electron density over all s bonds NH3 deki sp3 hibrit orbitalleri Bağ açısı 107o H2O daki sp3 hiprit orbitalleri Bağ açısı 105o The sp2 hybrid orbitals in BF3 BeCl2 daki sp orbitalleri Atomik orbitaller hibrit orbitalleri Orbital Diyagramları orbital diyagramları bağ açısı 180o doğrusal PCl5 deki sp3d hibrit orbitalleri PCl5 sp3d sp3d sp3d sp3d sp3d Neon 2 3s 3px 3py 3pz dxz dyz 90o 120o 120o dxy dx2-y2 dz2 Hybridized Promoted Trigonal Bipyrimidal Phosphorus Pentachloride: Phosphorus SF6 deki sp3d2 hiprit orbitalleri s bond remaining p orbitals from sp or sp2 p bond hinders rotation about the carbon-tocarbon bond Planar molecule (each carbon is trigonal planar) with p cloud above and below the plane formation of p bond Figure 11.10 The s and p bonds in ethylene (C2H4) overlap in one position - s p overlap - p electron density s + px + py = 3 sp2 orbitals H H C O Pz orbital H H C O H H H C O C H O H H C O H H C O CH2O 120o 1s 2s 2px 2py 2pz Promoted sp2 sp2 sp2 Hybridized 120o 120o Trigonal Planar 2s + 2px + 2pz Formaldehyde: Carbon 1s 2s 2px 2py 2pz Lone Pairs sp2 sp2 sp2 Hybridized 120o 120o Trigonal Planar 2s + 2px + 2pz Formaldehyde: Oxygen Formaldehyde p bond Sigma bond 2 Lone Pairs SP MELEZLEŞMESİ Figure 11.11 The s and p bonds in acetylene (C2H2) overlap in one position - s p overlap - p Multiple Bonds • A double bond (2 pairs of shared electrons) consists of a sigma bond and a pi bond. • A triple bond (3 pairs of shared electrons) consists of a sigma bond and two pi bonds. => s + px = 2 sp orbitals H Py orbital Pz orbital C N s + px = 2 sp orbitals H H C N C N 1s 2s 2px 2py 2pz Promoted sp sp Hybridized Linear 2s + 2px Hydrogen Cyanide: Carbon 1s 2s 2px 2py 2pz sp sp Hybridized Linear 2s + 2px Hydrogen Cyanide: Nitrogen p bond p bond O2 ve F2 için O2 paramanyetik Atom numarası 3-7 arası moleküller için, (Li2, Be2, B2, C2 ve N2) moleküler orbital enerji diyagramı C2 nin diamanyetik olduğu elektronların bu düzendeki orbital diyagramına yerleştirilmesiyle anlaşılır. Farklı İki Atom Arasındaki Molekküllerin Moleküller Orbitalleri Eğer molekülde oksijen varsa (CO gibi) aşağıdaki enerji diyagramı kullanılır.