the spontaneous emission of radiation accompanying a nuclear reaction
a radioactive isotope
a type of radioactive emission consisting of electrons. Stream of particles repelled by negative charged electrode and attracted to positive charge
type of radioactive emission consisting of a stream of high energy photons. Unaffected by either positive or negatively charged electrodes
a nuclear reaction that converts a proton into a neutron plus an ejected positron
a type of radioactive emission; a helium nucleus. Consists of a stream of electrons repelled by positively charged electrodes and attracted to negatively charges. Have mass to charge ratio identifying them as helium nuclei 42He2+.
a general term for both protons and neutrons
a nuclear reaction in which a proton in the nucleus captures an inner-shell electron and is thereby converted into a neutron
showed that there were three common types of radiation with markedly different properties, alpha, beta, and gamma
Ernest Rutheford (1871-1937) in 1897
the range of different kinds of electromagnetic radiation
the number of wave maxima that pass by a fixed point per unit of time
the length of a wave from one maximum to the next
a waves height measured from the midpoint between peak and trough
an equation that accounts for all lines in the hydrogen spectrum
the ejection of electrons from a metal on exposure to radiant energy.Photons – The smallest possible amount of radiant energy; a quantum
(h) 6.626 x 10-34J x s; a fundamental physical constant that relates energy to frequency, E=hv.
the amount of energy necessary to eject an electron from a metal
the smallest possible amount of radiant energy
an equation that relates mass, wavelength, and velocity, m=h/lv
De Broglie hypothesis
a model of atomic structure that concentrates on an electrons wave-like properties.
Quantum mechanical model
the position and the velocity of an electron can never both be known beyond a certain level of certainty.
Heisenbergs uncertainty principle
a grouping of orbitals according to principle quantum number
a grouping of orbitals by angular-momentum quantum number
a region where a wave has zero amplitude
(ms) a variable that describes the spin of an electron, either +1/2 or – ½.
Spin quantum number
No two electrons in an atom can have the same four quantum numbers.
Pauli exclusion principle
a set of rules that guides the electron filling order of orbitals in atoms.
the lowest-energy electron configuration of an atom.
Ground-state electron configuration
having the same energy level.
If two or more orbitals with the same energy are available, one electron goes into each until all are half full. The electrons in each of the singly occupied orbitals must have the same value for their spin quantum number.
an element in groups 1A or 2A, in which s orbitals are filled.
an element in groups 3A-8A, in which p orbitals are filled.
a transition metal orbital in which d orbitals are filled.
a lanthanide or actinide element in which f orbitals are filled.