CHE 1000: Introductory Chemistry
2019/2020 Academic Year
1. Bonding in Organic Compounds Part 2: MO Diagrams
Molecular Orbital (MO) Diagrams/Pictures of some compounds:
1. Ethane
2. Ethene
3. Ethyne
4. Benzene
5. How to draw MO Diagrams/Pictures of Organic Molecules
6. How to draw structure from MO picture (refer to textbook)
7.
Bond lengths and bond angles
in aliphatic compounds
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1. Types of Carbons in Organic Compounds (based on hybridisation
There are only 3 types of carbons in all known over 10,000,000
compounds of carbon, namely sp3, sp2 and sp carbon:
(i) sp3 Carbon: has 4 sp3 hybrid orbitals , no pure s or p orbital
(ii) sp2 Carbon: has 3 sp2 hybrid orbitals and 1 pure p orbital
(iii) sp Carbon: has 2 sp hybrid orbitals and 2 pure p-orbitals
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2. MO Pictures: (a) Alkanes, Example: Ethane, C2H6 (C-C single bond
Ethane:
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Free Rotation about C-C Single Bond
Ethane
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3. MO Picture of Alkene Double Bond: Ethene, C2H4
Ethene
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Ethene (C2H4) – Orbital Picture
Ethene
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Bonding in Ethene, C2H4
Bonding
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4. MO Picture of C-C Triple Bond: Ethyne (Acetylene), C2H2
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Ethyne (C2H2) – MO Picture
Ethyne
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5. MO Picture of Benzene (C6H6)- Aromatic Hydrocarbon
Benzene:
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MO Picture of Benzene (C6H6)
Benzene:
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6. Bond Lengths and Bond Angles in Aliphatic Compounds
Bond characteristics
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