Tetrahedral Electronic Geometry AB 3 U Species One

Tetrahedral Electronic Geometry: AB 3 U Species (One Lone Pair of Electrons on A) ¢ Some examples of molecules with this geometry are: NH 3, NF 3, PH 3, PCl 3, As. H 3 ¢ These molecules are our first examples of central atoms with lone pairs of electrons. Thus, the electronic and molecular geometries are different. All three substituents are the same but molecule is polar ¢ NH 3 and NF 3 are trigonal pyramidal, polar molecules. 1

Tetrahedral Electronic Geometry: AB 3 U Species (One Lone Pair of Electrons on A) Valence Bond Theory 2

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Molecular and Electronic Geometry 5

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Molecular Geometry 7

Tetrahedral Electronic Geometry: AB 3 U Species (One Lone Pair of Electrons on A) Polarity 8

Tetrahedral Electronic Geometry: AB 2 U 2 Species (Two Lone Pairs of Electrons on A) ¢ Some examples of molecules with this geometry are: H 2 O, OF 2, OCl 2, H 2 S ¢ These molecules are our first examples of central atoms with two lone pairs of electrons. Thus, the electronic and molecular geometries are different. Both substituents are the same but molecule is polar ¢ Molecules are angular, bent, or V-shaped and polar. 9

Tetrahedral Electronic Geometry: AB 2 U 2 Species (Two Lone Pairs of Electrons on A) Valence Bond Theory (Hybridization) O [He] 10 2 s 2 p Þ four sp 3 hybrids

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Polarity 12

Tetrahedral Electronic Geometry: ABU 3 Species (Three Lone Pairs of Electrons on A) ¢ Some examples of molecules with this geometry are: HF, HCl, HBr, HI, FCl, IBr ¢ These molecules are examples of central atoms with three lone pairs of electrons. Again, the electronic and molecular geometries are different. ¢ Molecules are linear and polar when the two atoms are different. Cl 2, Br 2, I 2 are nonpolar 13

Tetrahedral Electronic Geometry: ABU 3 Species (Three Lone Pairs of Electrons on A) Dot Formula (HF) Electronic Geometry (HF) 14

Tetrahedral Electronic Geometry: ABU 3 Species (Three Lone Pairs of Electrons on A) Molecular Geometry (HF) Polarity (HF) 15

Tetrahedral Electronic Geometry: ABU 3 Species (Three Lone Pairs of Electrons on A) Valence Bond Theory (Hybridization) F [He] 16 2 s 2 p Þ four sp 3 hybrids

Trigonal Bipyramidal Electronic Geometry: AB 5, AB 4 U, AB 3 U 2, and AB 2 U 3 § Some examples of molecules with this geometry are: PF 5, As. F 5, PCl 5, etc. ¢ These molecules are examples of central atoms with five bonding pairs of electrons. The electronic and molecular geometries are the same. ¢ Molecules are trigonal bipyramidal and nonpolar when all five substituents are the same. If the five substituents are not the same, polar molecules can result, As. F 4 Cl is an example. 17

Trigonal Bipyramidal Electronic Geometry: AB 5, AB 4 U, AB 3 U 2, and AB 2 U 3 Valence Bond Theory 18

Trigonal Bipyramidal Electronic Geometry: AB 5, AB 4 U, AB 3 U 2, and AB 2 U 3 19

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Molecular Geometry Trigonal Bipyramidal 21

Polarity 22