Hybridization: The Shape Of Things To Come pairs hydrogen sulfide electronic structure bondslone...
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Transcript of Hybridization: The Shape Of Things To Come pairs hydrogen sulfide electronic structure bondslone...
B. Electron Counting InAtoms
neon potassium silicon
1s2 1s22s22p63s23p6 1s22s22p62s22p6 4s1 3s23p2[Ar] or
nitrogen carbon hydrogen
1s2 2s2 2p3 1s2 2s2 2p2 1s1
fluorine bromine chlorine
1s2 2s2 2p5 [Ar] 3d10 4s24p5 1s2 2s2 2p6 3s2 3p5
oxygen sulfur boron
1s2 2s2 2p4 1s2 2s2 2p6 3s2 3p4 1s2 2s2 2p1
InMolecules,andValency 2 electrons in the first shell, 8 in the second, 16 in the third. share completely donate or receive electrons. each hydrogen atom has 2 first shell electrons One bond containing 2 electrons is formed in this sharing process valency of hydrogen in H2 is 1 He C ___4____ N ___3____ O ____2___ F ___1____ Cl ___1____ Br ___1____ S ___2____ may only bring 1 common molecules is 1. C ___CH4__ N __NH3___ O __H2O___ F __HF____ Cl ___HCl___ Br __HBr____ S __H2S___
N 2s22p12p12p11s11s11s1 H3
The blue and red electrons are shared in bonds, two per bond, so ammonia has two electrons that are not in bonds, ie a lone pair.
H2 1s11s12p12p12p12p12s2 O 2 2 H 1s12p12p12p12p12p12s2 F 1 3
1 3 H 1s14p14p14p14p14p13d104s2 Br C 2s22p12p11s11s11s11s1 H4 4 0
favored electron count for that is 8 B 2s22p11s11s11s1 H3 3 0 H2 1s11s13p13p13p13p13s2 S 2 2
Si 3s23p13p11s11s11s11s1 H4 4 0 P 3s23p13p13p11s11s11s1 H3 3 1
electrons is lost
C. Mixing Atomic Orbitals To Maximize Overlap In Molecules Combinings-andp-Orbitalscalled atomic orbitals. have different shapes as atomic orbitals.
waterelectronic structure
bonds lone pairs hydrogen fluorideelectronic structure
bonds lone pairs
hydrogen bromideelectronic structure
bonds lone pairs methaneelectronic structure
bonds lone pairs
boraneelectronic structure
bonds lone pairs hydrogen sulfideelectronic structure
bonds lone pairs
tetrahydrosilaneelectronic structure
bonds lone pairs phosphineelectronic structure
bonds lone pairs
hybridized to make them. 2 molecular orbitals, of three gives 3, and of n gives n. denoted as sp, whereas sp2 surfaces are formed if two p-orbitals are mixed with one s-. a ___sp3 __ hybrid. GeometricShapes
the boy in the middle. girl-boy-girl angle is 180 ideal bond angle. middle of a triangle with then 120°. a tetrahedron, 109°.
s- d- d- p-
straight line connecting three dots a triangle a square
a tetrahedron a trigonal bipyramid an octahedron
ShapesOfMoleculesBasedOnGeometricShapes2 sp-hybrid orbitals. 3 hybrid orbitals, and 4 arise from. Bold lines mean dashed lines
will be sp2 hybridized. A tetrahedron of sp3 hybrids if 4 bonds sp hybrid orbitals. 0 lone pairs it is tetrahedral. 3 lone pairs. 4 entities hydrogen fluoride is approximately tetrahedral. Water 4 objects tetrahedral hydrogen chloride, 4 Cl is tetrahedral
sp3 sp2 sp
ammonia, 4 tetrahedral hydrogen sulfide, 4 tetrahedral arrangement; and, borane, 3 triangular arrangement. C in methane is tetrahedral with a dihedral angle of 109° O in water is tetrahedral with a dihedral angle of 109° Br in hydrogen bromide is tetrahedral with a dihedral angle of 109° N in ammonia is tetrahedral with a dihedral angle of 109° S in H2S is tetrahedral with a dihedral angle of 109° B in BH3 is trigonal with a dihedral angle of 120°
an sp hybrid consisting of 2 MOs in a linear arrangement with a dihedral angle of 180°
3 sp2 MOs, and these arrange in a trigonal arrangement with a dihedral angle of 120°
4 sp3 MOs, and these arrange in a tetrahedral arrangement with a dihedral angle of 109°
sp sp2 sp3
HC
H
H H
water hydrogen fluoride methane
HO
Heg
HF
hydrogen sulfideHBr BH3
HBr B
HS
H
PH3 SiH4 CCl4
HP
H
H
HSi
H
H H
ClC
Cl
Cl Cl
D. Multiple Bonds 8 electrons in its second shell 7 electrons in its second shell; this is not a are relatively reactive. sp3 hybridized
H
CH
H sp3 sp2
CHH
H
s-bonded sp hybridized C-atoms
are called sigma. pi bond. Maximal overlap is achieved Perpendicular p-orbitals do interact. of a p bond. 1 line(s), and p-bonds are represented by adding 2 parallel line(s).
because they would not contribute to the binding interaction. Atoms in molecules can selectively
CC
ethene before mixing p-orbitals
CC
ethene after mixing p-orbitals
OO
OH
NH O
OH
OH
# __2__isoprene
# __2__pyruvic acid
# __1__an imine
# __1__lactic acid
# _3___benzene
# __1__β-pinene
Carbene, CH2, 6 shared electrons in the C-second shell. this is called the singlet state. Alternatively, carbenes can be sp2-hybridized with one electron in each of the hybrid lobes that does not point to a hydrogen; this is a triplet state.
s-bonded sp hybridized C-atoms
H
CH
triplet
CH H C
unstable triplet singlet
CH
ethyne before mixing p-orbitals
C H CH
ethyne after mixing p-orbitals
C H
two p bonds surrounding the s bond called a triple bond.
it does not matter if. are sp hybridized, three sp2, and four sp3.
# __1__propyne
# __1__1-butyne
# __1__2-butyne
# __0__butane
# __1__acetonitrile
# __2__1,3-butadiyne
N
propane hexane methylcyclohexane
H3C
H2C
CH3 H3C
H2C
CH2
H2C
CH2
CH3
H2CH2C C
H2
CH2
CH2sp3 sp3
sp3
CHCH3 sp3
sp3
acetone 1-pentene 1-methylcyclohexene
H3CC
CH3 H3C
H2C
CH
HC
CH2
CH3
H2CH2C C
H2
CH2
CHsp2 sp2
sp3
CCH3 sp2
sp3
O
sp2 sp2
acetic acid cis-1-hydroxy-2-butene
H3CC
CH3 HO
H2C
CH
HC
CH2
CH3
H2CH2C S
CH2
CHCOH
Osp2sp2
sp2sp2sp2 sp3
sp3
sp3
H3CC
CH2
H2C
CH2
H2C
CH3
O HCHC
CH
CHC
HC Cl
H3C C C CH2H2C OH
sp3sp2sp2
sp3
sp2
sp
sp3
OCH3CHCCH3
CHC
HC C
HC C O CH3CHC
HCC
H
naproxen
OHCP
OHHO
O
P OHOH
O
H2C CH2
H2C NH2
alendronate
O OH
CHCHC
HC CHC O CH3
O
aspirin
sp2sp3
sp2
sp3
sp3
sp3
sp3sp2 sp3
sp3
sp3
CH3CC
HNH
CH2CH
CNN+
-NCHCH2HO
O
OHN O
zidovudine (AZT)
sp2
spsp2