Fundamentals of Organic Chemistry Chapter 1

What is Organic Chemistry? Old Timers View: Something with vital forces! Now: Chemistry of carbon-containing compounds

Atoms, Molecules, and Bonds Atoms  Nucleus (Neutron, protons) Electron

Atomic number (Z): Number of protons in specified element Mass number (A): Sum of the numbers of proton and neutron Isotope (?): Element with the same Z but different A (different # of neutron) Atoms, Molecules, and Bonds

Difference between isotopes Example: U 235 and U 238 Spontaneous nuclear fission ?

Shells and Orbitals The motion of electron can be described in the form of mathematical equation The solution of equation as wavefunction. Also called orbital (probabilistic distribution of electrons in space) The orbitals are stratified in difference layer (shell)

Shells and Orbitals

Filling electron(s) in orbital

Rules of Electron Arrangement Rule 1: 1s  2s  2p  3s  3p  4s  3d Two electrons in an orbital with opposite spin One-by-one half-fill then full

Chemical Bonds Ionic bond: Electrostatic interaction, Charged components Covalent bond: Sharing electrons between components * Valence shell electron and octet rule

From atomic to molecular orbital For the chemical bond, valence shell electron participates To form covalent bond, electrons in atomic orbital are re-arranged (hydridized), giving new form of wavefunction

From atomic to molecular orbital

sp3, sp2, sp hybridization and bond

Polarity and Electronegativity

Example of non-equivalent electron distribution in polar covalent bond

Acid and Base Representative definition of acid/baseRepresentative definition of acid/base -Bronsted-Lowry acid/base: acid: release proton base: accept proton -Lewis acid/base acid: accept electron pair base: donate electron pair