Unit 1 Flashcards
Describes Atoms as Tiny, Indestructible, Particles with no internal structures
Dalton
Discovered atom and continued on with his plum pudding model given his vision of electrons embedded in a sphere of positive charges.
Thompson
Rutherford
Discovers the atom has a small dense, positively charged nucleus with electrons moving around the nucleus
Problem of Rutherford model
could not explain electron movements and color change of objects when heated
Neil Bohr
electrons orbits around nucleus in circular pathway with set sizes and energy
Bohr problem
Makes poor predictions regarding larger atoms
Does not predict intensities and spectral lines
Does not explain fine structure and hyperfine structure
Energy Level
The fixed energies electrons can have
Quantum:
Amount of energy required to move electron from one energy level to another energy level
Quantum Mechanical Model
Determines the allowed energies an electron can have and how likely it is to find the electron in various locations around the nucleus
How is Mechanical model represented?
Represented as a cloud due to the volume of space sorrounding the nucleus and the probability of finding the eletrons around it
Atomic Orbitals
Region of space in which there is a high probabbility of finding an electron
SPDF(shape) and maximum electrons
S- Sphere (2 electrons)
P-Dumbbell (6 electrons)
D- Clover (10 electrons)
Electron Configuration
Electrons arranged in various orbitals around nuclei of atoms
Aufbau Principle
Electrons occupy orbitals of lowest energy
May contain at least 2 electrons with opposite spins
Pauli exclusion
Hund’s rule
Electrons occupy orbitals in a way that makes the # of the same spins as large as possible
Atomic Size
protons are being added to the nucleus, making it more positively charged by pulling electrons in making it smaller (left to right)
(up, down), the number of energy levels (n) increases, so there is a greater distance between the nucleus and the outermost orbital. This results in a larger atomic radius
Cation smaller cause of losses Anions bigger because it gained electrons
ion size trend
Ionization energy
Increase (left to right) = Electron cloud is closer to nucleus attracting (more energy) electrons. Decrease (up, down) = Distance is greater between nucleus and the cloud decreasing attraction (less energy) to remove electrons
Electronegativity
Increase (left to right) = Atoms in the left tend to be more than half full attracting electrons and high electronegativities
Decrease(up,down)=Increased distance weakens attraction and electronegativity
Non-metals Properties
Poor conductors of heat, Not luster or shiny
Metals Properties
Luster Shiny, heat and electricity Conductors
