Midterm Structure 1 and 2 Concepts

• protons


  positively charged particles in the atom
• neutrons


  particles in the atom with no charge
• electrons


  negatively charged particles in the atom
• mass number


  total number of protons and neutrons in an atom
• atomic number


  number of protons in an atom
• isotopes


  atoms of the same element with different numbers of neutrons
• ions


  atoms or molecules with a net electrical charge
• relative atomic masses


  average mass of all the isotopes of an element, taking into account their abundance
• mass spectra


  graph showing the abundance of each isotope in a sample
• structure of the atom

  arrangement of protons, neutrons, and electrons in an atom
• Democritus


  proposed the idea of atoms as indivisible particles
• Antoine Lavoisier


  proposed the law of conservation of mass
• James Dalton


  determined that elements exist as discreet packets of matter
• Eugen Goldstein


  discovered that cathode ray tubes emitted light from the positive electrode
• J.J. Thompson


  estimated the mass of rays and discovered negatively charged particles
• plum pudding model


  model proposed by J.J. Thompson where negatively charged particles are embedded in a positively charged sphere
• Ernest Rutherford


  used the gold leaf experiment to discover that atoms are mostly empty space and contain protons
• Niels Bohr


  proposed the planetary model of the atom with electrons orbiting a central nucleus
• Heisenberg


  discovered the uncertainty principle and the concept of orbitals
• momentum


  the product of an object's mass and velocity
• subatomic particle


  a particle smaller than an atom, such as an electron or proton
• quantum theory


  theory that describes the behavior of subatomic particles
• orbitals


  regions of space around the nucleus where electrons are likely to be found
• EMS spectrum acronym

  red martian invade venus using x-ray guns, from longest wavelength/lowest frequency to shortest wavelength/highest frequency
• hydrogen electrons transitioning to n=2 emit

  visible light
• hydrogen electrons transitioning to n=1 emit

  UV radiation
• hydrogen electrons transitioning to n=3 e4mit


  IR radiation
• removing an electron in a singly occupied orbital vs a full one

  requires more energy bc the full orbital has two electrons that repel each other
• 1dm^3


  1000cm^3
• concentraton

  mass in grams/volume in dm^3
• Morality (M0

  = moles of solute (moll)/ vol of solution dm^3
• C1V1=


  C2V2
• avogadros law

  equal volumes of gases at the same temperature and pressure wil contain the same number of as particles
• ideal gas assumptions

  1) volume of particles is zero 2) particles are in constant motion 3) particles undergo elastic collisions (no loss of ke) 4) gas particles exert no attractive or repulsive forces on each other.
• STP formula for mol and vol

  Amount (mol) = volume (dm^3)/22.7dm^3mol^-1
• boyles law


  P1V1=P2V2
• Charles law


  V1/T1=V2/T2
• Gay-Lussac's law


  P1/T1=P2/T2
• ideal gas equation

  PV=nRT, n is amount of gas in mols, R is unerversal gas constant
• ideal gas equation for molar mass

  M=mRT/PV m is mass of gass in gramsM is molar mass