Unit 1 Introduction to Organic Chemistry Flashcards
Origin of Organic Chemistry
- Foundations date from mid-1700’s
- Compounds obtain from plants and animals
- Low-melting solids
- Hard to isolate, purify, and work with
- considered to have some vital force as they were from living sources
- though that could not be synthesized in lab
In 1816 he found out that soap can e separated into several organic compounds which he termed fatty acids
Chevreul
In 1828 he showed that it was possible to convert organic salt ammonium cyanate into organic substance urea
Wohler
the study of carbon compounds, more than 50M known chemical compounds contain carbon
organic chemistry
It is a group 4A element that can share 4 valence electrons and form 4 covalent bonds.
Able to bond with one another to form long chains and rings.
The only element that has the ability to form immense diversity of compounds
Carbon
Bonding is almost covalent
May be gases, liquids, or solid with low melting points (less than 360’C)
Most are insoluble in water
Most are soluble in organic solvents such as diethyl ether, toluene, and dichloromethane
Aqueous solutions do not conduct electricity
Almost all burn
Reactions are usually slow
Organic Compound
Most have ionic bonds Most are solids with high melting points Many are soluble in water Almost all are insoluble in organic solvents Aqueous solutions conduct electricity Very few burn Reactions are often fast
Inorganic Compounds
consist of Nucleus = proton+ neutron (contains essentially all the mass of the atom) and Electron
Atom
diameter of an atom
2x10-10m or 200 picometers
Angstrom is 10-10m =100 pm
number of protons or electrons in an atom’s nucleus
atomic number (Z)
number of protons plus neutrons
mass number (A)
weighted average mass in atomic mass units (amu) of an element’s naturally occurring isotope
atomic mass or atomic weigt
atoms with the same atomic number but different mass numbers
Isotopes
mathematical equation that describes the behavior of a specific electron in an atom
wave equation
the solution of wave equation denoted by Greek letter psi
wave function or orbital
4 kinds of orbitals:
s orbitals -spherical, nucleus at the center
p orbitals -dumbbell-shaped, nucleus at the middle (px, py, or pz)
d orbitals -elongated dumbbell-shaped, nucleus at the center
f orbitals
atomic structue - orbitals:
orbitals of an atom are organized into different electron shells
centered around the nucleus in shells of increasing size and energy
different shells contain different numbers and kinds ff orbitals
each orbital can be occupied by 2 electrons
atomic structure: electron configuration:
ground-state electron configuration: listing of orbitals occupied by an atom’s electrons
called lowest-energy arrangement
lowest energy orbitals fill first in order of 1s-2s-2p-3s-3p-4s-3d
Aufbau principle
electrons act as if they were spinning around an axis
spin can have only 2 orientations up and down
only 2 electrons can occupy an orbital, and they must be of opposite spin
Pauli exclusion principle