A | B |
cathode | negative electrode in Crooke’s tube |
anode | positive electrode n Crooke’s tube |
cathode ray | glowing beam of charged particles coming from the cathode of Crooke’s tube |
JJ Thomson | discovered the electron using Crooke’s tube |
Eugene Goldstein | discovered the proton using a modified Crooke’s tube |
Plum Pudding Model of Atom | atomic model of Thomson described as having negative charges spread out among an equal number of negative charges |
Robert Milligan | determined the charge on an electron in his oil drop experiment |
alpha radiation | deflected by a magnetic field is composed of particles with mass of 2 amu and charge of +2 |
beta radiation | deflected by a magnetic field is composed a stream of electrons with negative charge |
gamma radiation | not deflected by a magnetic field is composed of pure energy like X-rays |
Ernest Rutherford | bombarded gold foil with alpha particles leading to Nuclear Model of atom |
Gold Foil Experiment | most alpha particles deflected, few bounce back, atom mostly empty space with a small dense positively charged center |
Nuclear Model of Atom | protons and neutron in dense central area, the nucleus, surrounded by freely orbiting electrons as proposed by Rutherford |
Solar System Model of Atom | alternate explanation of nuclear model proposed by Rutherford emphasis on electrons freely orbiting nucleus |
James Chadwick | discovered the neutron |
continuous spectrum | rainbow of colored light produced when white light is passed through a prism |
wavelength | the distance between peaks of consecutive light waves represented by Greek letter lambda (λ) |
frequency | number of peaks that pass a particular point in one second represented by Greek letter nu (ν) |
line spectrum | specific pattern of colored lines emitted by excited electrons unique to each element |
spectroscope | instrument used to view line spectra of elements |
quantum theory | proposed by Max Planck that light energy is not emitted continuously but in discrete packets |
quantum | a discrete package of electromagnetic energy |
photon | a discrete package of light energy |
Energy Level Model of Atom | proposed by Neils Bohr modified Nuclear Model by explaining electrons were found on specific energy levels |
excited state | electron absorbing a discrete amount of energy is raised to higher energy level |
ground state | electron found in the lowest energy level possible |
valence shell | outermost energy level in an atom that contains 1 or more electron |
valence electrons | electrons in an atoms outermost energy level |
ion | a charged atom that has lost or gained an electron |
Louis de Broglie | waves can act like particles and particles can act like waves |
Heisenberg Uncertainty Principle | can not know the location and velocity of an electron at the same time |
classical mechanics | study of the motion of large particles |
quantum mechanics | study of the motion of small particles |
quantum (electron cloud) model of the atom | electrons are founding “probable” locations consisting of sublevels and orbitals known as electron clouds |
Lewis electron-dot symbols | diagrams used to represent the valence electrons of an atom or ion |
principal quantum number | describes the outermost energy level an electron occupies |
second quantum number | describes the sublevel with in an energy level an electron occupies |
third quantum number | describes the orbital within the sublevel of an energy level occupied by the electron |
fourth quantum number | describes the spin of the electron in its orbital |
alkali metal | elements in group 1 with 1 valence electron and an oxidation number of +1 |
alkaline earth metals | elements in group 1 with 2 valence electrons and an oxidation number of +2 |
sublevels | name given to subdivisions of energy levels |
orbitals | name given to subdivisions of sublevels in an energy level |
Pauli exclusion principle | electrons cannot occupy the same energy level unless they have opposite spins |
name and identify how many sublevels are on the first energy level | one level the s sublevel |
name and identify how many sublevels are on the second energy level | two levels the s and p sublevels |
name and identify how many sublevels are on the third energy level | three levels the s, p, and d sublevels |
name and identify how many sublevels are on the fourth energy level | three levels the s, p, d and f sublevels |
how many orbitals are in an s sublevel | 1 |
how many orbitals are in a p sublevel | 3 |
how many orbitals are in a d sublevel | 5 |
how many orbitals are in a f sublevel | 7 |
how many electrons can occupy an s sublevel | 2 |
how many electrons can occupy a p sublevel | 6 |
how many electrons can occupy a d sublevel | 10 |
how many electrons can occupy a f sublevel | 14 |
what is Hund’s rule | electrons do not pair up in an orbital until each orbital in the sublevel has at least one electron |