# Equations and Theories

 law conservation of mass
 total of mass and energy stay the same in any charge
 law of multiple proportions
 when different compounds are formed by using the same elements, different masses combine in a particular whole number ratio.
 dalton’s atomic theory
 atoms are made of indivisible particleschemical reactions involve rearrangements of atomsatoms of diff. elements combine to form compounds
 aristole known for ?
 all substance is made of 4 elemnts,water earth fire wind
 atom
 smallest particle of an ELEMENT
 who made cathode ray tube? what does tube do?what is he known for ?
 J.J thompson air is pumped outplum pudding model, discovered electrons
 Ernest Rutherford
 discovered postitive piece in center, nucleuselectrons would surround itatom is empty
 neutron is same mass as … ?
 proton
 alpha particle
 positively charged piecesshot at florescent screen it glowsdeflected by positive pieces.
 nucleus in weight.
 small volume, big mass and density
 the atomic number says
 the number of protons
 mass number is…
 protons +neutronsaccount for most of mass
 isotope
 atoms of same element can have diff number of NEUTRONSCHANGES mass number
 how to get average
 multiply atomic mass number (isotope) by percentage abundance then add them together
 study of light led to
 quantum mechanical model
 speed of light
 3.00 x 10^8 m/s
 v =
 frequency
 lambda =
 wavelength
 frequency is expressed in what units
 seconds or hertz
 equation for frequency
 speed of light=wavelength(frequency)
 emission spectra or photoemission
 when light is given off by electron falling from high energy level to low energy level.
 metric unit of energy ?
 Joules
 equation to find wavelength
 frequency = wavelength (speed of light)
 equation to find energy of photon
 E=planks constant (frequency)
 bohrs model
 equation to find wavelength of a particle
 lambda = planks constant / mass(frequency)
 Heisenburg uncertainty principle
 it is impossible to know exactly the location and velocity of a particle.
 bohrs model
 Planetery modelamount of energy sperate one level from anothermove around like planets
 what is quanta
 quna is the amount of energy needed to move energy levels
 principle quantum number
 energy level1,2,3
 atomic orbital
 like electron cloudwhere you would find electron
 sublevels
 s,p,d,f
 aufbau principle
 electrons enter the lowest energy first
 Pauli exclusion principle
 at most 1 electron per orbital- different spins
 hunds rule
 when electrons occupy orbitals they cannot pair up until they have to