| organic compounds | compounds derived from living organisms
contain "vital force"-the essence of life |
| inorganic compounds | compounds derived from minerals
lacking vital force |
| Friedrich Wohler | He succeeded in obtain of urea from inorganic compound (ammonium cyanate)
till then it was assumed that organic compound can't be obtained from inorganic compounds
He obtained it with mistake |
| atoms | smallest particle which can't be further divided |
| protons | positive charge
mass= 1.673*10 -27kg |
| electrons | negative charge
mass=9.109*10 -31kg |
| neutron | no charge
mass =1.673*10 -27kg |
| atom have an internal structure consisting of one or more subatomic particles: | protons
neutrons
electrons |
| smallest particle is | electron |
| biggest area of atom is | empty because electrons move around the nucleus |
| protons and nucleus are placed in | nucleus |
| biggest mass of the atom is | in nucleus |
| nucleus | most of the mass of an atom is concentrated in |
| nucleus contains | one or more positively charged protons &
one or more neutrons with no electrical charge |
| shells are | negative because of electrons |
| one or more negatively charged | electrons are in constant motion somewhere outside the nucleus |
| the number of electrons | equal to the number of protons |
| do atom has electrical charge | no atom has no overall electrical charge |
| by adding or removing electrons from atoms | we will obtain ions positive or negative |
| an atom is mostly | free space because the volume of the nucleus and electrons outside the nucleus are extremely small compared to the overall volume of the atom |
| heisenberg uncertainty principle | it is not possible to determine both the position and the momentum of an electron |
| Wave function | describes the energy of an electron and the probability of finding the electron in a region around the nucleus |
| atomic orbital | the probability distribution about one atomic nucleus
wave function=atomic orbital |
| amplitudes | numerical magnitudes |
| signs | positive or negative |
| nodes | values of wave function equals zero (given by quantum numbers) |
| atomic orbitals | s, p, d, f |
| pauli exclusion principle | no two electrons can have identical quantum numbers |
| each atomic orbital can have | at most two electrons |
| aufbau principle | atomic orbitals are filled with electrons from lowest potential energy to highest |
| degenerate orbitals | orbitals that have the same energy |
| hunds rule | the electronic configuration with the highest multiplicity is more stable |
| multiplicity | most unpaired spins |
| electron configuration | of an atom describes what orbitals the electrons occupy |
| rules for determination an atoms electronic configuration | 1. an electron always goes into the available orbital with the lowest energy
2. No more that two electrons can occupy each orbital and two electrons must be opposite spin |
| core electrons | electrons in inner shells |
| valence shell | electrons in the outermost shell |
| each shell presents what | quantum number |
| chemical bond | the forces holding atoms together in compounds |
| valence electrons | the electrons in the outer shell |
| lewis dot representation of atoms | dots around the chemical symbol of an atom represent the valence electrons |
| ionic bond | transfer of electrons from one atom to another
electrostatic attraction between oppositely charger ions |
| do all atoms transfer electrons from one atom to another to form ions | no, some atoms do not transfer electrons from one atom to another to form ions |
| covalent bond | consists of a pair of electrons shared between two atoms |
| electronegativity | is a measure of tendency of an atom to attract a bonding pair of electrons |
| polar covalent bonds | electronegativity differences in covalently bonded atoms results |
| how polarity of bond is determined | by the difference in electronegativity values |
| nonpolar | if the electronegativities are the same the bond is nonpolar and the electrons are shared equally |
| polar | if the atoms have greatly differing electronegativities the bond will be |
| electrostatic potential maps | are models that show how the charge is distributed in the molecule under the map |
| what do the colors indicate | the distribution of charge in the molecule |
| red | electron rich areas |
| blue | electron deficient areas-positive |
| green | signifies no charge |
| polar molecule | is a molecule that is electrically asymmetrical, causing it to be oppositely charged at two points |
| the molecule possesses a | molecular dipole |
| polar bonds | refers to a bond that shares its paired electrons unequally
the bond is therefore polar in that it has slightly more positive side and a slightly more negative side |
| polar molecule | has polarity based upon a net charge caused by the physical shape and electron distribution across the entire molecule.
The molecule therefore has a slightly more positive side and a slightly more negative side.
Polar bonds hold polar molecules together |
| lewis Octet rule | an atom is most stable if its outer shell is either filled or contains eight electrons and it has no electrons of higher energy |
| formal charge | is the difference between the number of valence electrons an atom has when it is not bonded to any other atom and the number of electrons it owns when it is bonded |
| fc= computing | number of valence e - (number of lone - pair electrons +1/2 number of bonding electrons) |
| what happens in formal charge for neutral molecule | the sum of the formal charges is zero. |
| what happens in formal charge for ion | the sum of the formal charges is equal to the charge charge of the ion |
| what is VSEPR and explain | valence shell electron pair repulsion. model combines the Lewis concept of shared electron pairs and lone pair electrons with the concept of atomic orbitals and adds a third principle: the minimization of electron repulsion |
| hybridization | process of obtaining hybrid orbitals |
| but what is hybrid orbital | hybrid orbitals are mixed orbitals that result from combining atomic orbitals |
