Unit 1 Flashcards
John Dalton
Matter is made of tiny indivisible particles called atoms
JJ Thomson
Atoms are uniformly positive (plum pudding)
Corpuscles
Electrons
Ernest Rutherford
Positively charged nucleus (solar system)
Max Planck
Black body radiation, energy is quantized
Albert Einstein
Light energy can be quantized (photon)
Photoelectric effect
High frequency light excited electrons from metals
Continuous spectrum
Contain all wavelengths in a particular region of the EM spectrum
Line spectrum
Contains only particular wavelengths and arises when excited electrons emit energy
Lowest possible energy state for an atom
Ground state
Proved that electrons had wave particle duality
Louis de Broglie
Came up with an equation for the probability of finding an electron in a given space
Ernest Schödinger
Impossible to know both the exact position and speed of an electro
Heisenberg uncertainty prnciple
Describes the size and energy of an atomic orbital
Principal quantum number
Orbitals can hold only two electrons with opposite spins
Pauli Exclusion Principle
Fill orbitals starting from the lowest available energy orbital
Aufbau principle
All orbitals in the same subshell must contain an electron before any two electrons can occupy an orbital
Hund’s Rule
Has the same electron configuration as each other (ex: Ca2+, S2-, Ar)
Isoelectronic
Using nearby vacant d orbitals to exceed 8 valence electrons past period 3 is called…
Expanded octet
These atoms can have an under filled octet
Be and B
A covalent bond in which the electrons involved in bonding are from one atom
Coordinate covalent bonding
The distribution of electrons is an average of that shown by various lewis structures
Resonance structures
Bold angle of linear structure
180
Bond angle of trigonal planar structure
120
Bond angle of tetrahedral structure
109.5
Bond angle of trigonal pyramidal structure
107
Bond angle of bent structure
104.5
A method to describe the geometry of a molecule based on the idea that electron pairs are as far apart as possible
VSEPR (Valence Shell électron pair répulsion) theory
The chemical bond within a molecule (ie covalent bonds)
Intramolecular forces
À force that causes one molecule to interact with another molecule
Intermolecular forces
Brittle, hard, conducts electricity when dissolved in water, high melting point
Ionic crystals
free moving electrons, malleable, electrically conductive, hard, shiny
Metallic crystals
Lower melting point and less hard than other ionic crystals, DON’T conduct electricity
Molecular crystal
Very high melting point, extreme hardness, DON’T conduct electricity
Covalent network crystal
Slippery black electric conductor, carbon atoms on hexagonal sheets, trigonal planar (sp2 hybridized)
Graphite
Very high melting point, extreme hardness, do not conduct electricity, tetrahedral (sp3 hybridized)
Covalent network crystal (diamond)
