| A | B |
|---|
| Thomson model of an atom | A ball of positive charge containing a number of electrons (plum pudding: neg elec in lump of pos pro). No explanation of # pro and neu or arrangement. |
| Rutherford model of an atom | Most of atom's mass in small, pos charged region : nucleus, rest empty space with electrons surrounding nucleus |
| Bohr model of an atom | Electrons travel around nucleus in definite orbits. Electrons have fuxed energy level |
| Orbits | concentric paths |
| Quantum mechanical model of an atom | No definite shape, no precise orbits for electrons. 90% probability clouds. the modern description of the electrons in atoms |
| energy level | the region around the nuclues where the electron is likely to be moving |
| Can electrons exist between energy levels? | NO |
| Quantum of energy | amount of energy required to move an electron from its present energy level to the next higher energy level |
| The higher the electron is placed on the energy ladder..... | the farther away from the nucleus it is |
| Are rungs equally spaced on energy ladder? | NO |
| How is the probability of finding an electron in a certain area in the QMM? | A fuzzy cloud |
| Principal quantum number | the principal energy level: 1,2,3, 4. ALSO number of sublevels within that principal energy level |
| Energy sublevels | what electrons occupy: s, p, d, f |
| atomic orbitals | the cloud shapes of probability of finding an electron in the QMM |
| nodes | in p orbitals, regions close the nucleus where probability is low |
| s shape | spherical |
| p shape | dumbell |
| electron configurations | the ways in which electrons are arranged around the nuclei of atoms |
| aufbau principle | electrons enter orbitals of lowest energy first |
| Are oribitals within a sublevel always =? | YES |
| Pauli exclusion principle | an atomic orbital may describe at most 2 electrons |
| Hund's rule | when electrons occupy orbitals of equal energy, one electron enters each orbital until all orbitals contain one electron with spins parallel (2nd added to each so paired spins) |
| electromagnetic radiation | includes radio waves, microwaves, visible light, infrared and ultraviolet light, xrays, gamma rays |
| amplitude | (of a wavelength) height of wave from origin to crest |
| wavelength | distance between crests |
| frequency | in a travelling wave, the number of wave cycles to pass a given point per unit of time |
| spectrum | when sunlight passes through a prism, light separates into a SPECTRUM of color |
| differences between visible light | red: longest wavelength, lowest frequency, blue: shortest wavelegth, greatest frequency |
| How does every element emit light if it is heated by passing electricity? | it absorbes energy, then loses it which emits as light |
| atom emission spectrum | (of an element) is given by passing the light emitted by an element through a prism (consists of relatively few lines) |
| What does each line of the atom emission spectrum correspond to? | one exact freqyency of light being given off, or one exact amt of energy being emitted |
| Is the emission spectrum of each element unique to the element, or does it repeat? | Unique |
| Energy to Frequency relationship: directly or inversely proportional? | directly |
| photons | light quanta |
| photoelectric effect | electrons called photoelectrons are ejected by metals when light shines on them |
| Photoelectric effect will only occur when? | When the frequency of light is above that of the threshold of energy |
| increase energy of photon in photoelectic effect | increase speed of electron |
| increase intensity of photon in photoelectric effect | increase number of photons striking metal |
| lyman series | lines at ultraviolet end (from higher to n = 1) |
| balmer series | lines in visible spectrum (from higher to n = 2) |
| paschen series | lines in infrared spectrum (from higher to n = 3) |
| How is energy absorbed or emitted? | In packages, quanta |
| How does light behave? | in Particles AND waves |
| de Broglie's equation | predicts that all matter exhibits wavelike motions |
| quantam mechanics | describes motions of subatomic particles and atoms as waves, and lose or gain energy in quanta |
| Heisenberg uncertainty principle | states that it is impossible to know exactly both velocity and position of a particle at the same time |
