Atomic Structure & Periodicity
60 terms · page 2 of 3
Heisenberg Uncertainty Principle
The principle that the position and momentum of a particle cannot both be known to arbitrary precision at the same time.
Atomic Structure & PeriodicityHund's Rule of Maximum Multiplicity
The rule that electrons occupy degenerate orbitals singly with parallel spins before any orbital is doubly occupied.
Atomic Structure & PeriodicityInner Transition Element
An element of the lanthanide or actinide series, in which f orbitals are being filled.
Atomic Structure & PeriodicityIonic Radius
The effective radius of an ion within a crystal lattice, deduced from measured interionic distances.
Atomic Structure & PeriodicityIonisation Energy
The minimum energy needed to remove the most loosely held electron from one mole of gaseous atoms in their ground state.
Atomic Structure & PeriodicityIsobar
One of a set of atoms of different elements that share the same mass number but have different atomic numbers.
Atomic Structure & PeriodicityIsoelectronic Species
Atoms or ions that possess the same number of electrons and the same electron configuration.
Atomic Structure & PeriodicityIsotone
One of a set of nuclides that contain the same number of neutrons but different numbers of protons.
Atomic Structure & PeriodicityIsotope
One of two or more atoms of the same element that differ in neutron number and therefore in mass.
Atomic Structure & PeriodicityMagnetic Quantum Number
The quantum number mₗ that specifies the spatial orientation of an orbital relative to an applied magnetic field.
Atomic Structure & PeriodicityMass Number
The total number of protons and neutrons in an atomic nucleus.
Atomic Structure & PeriodicityMetallic Character
The tendency of an element to lose electrons and display typical metallic properties such as lustre, malleability and conductivity.
Atomic Structure & PeriodicityMetalloid
An element with properties intermediate between those of metals and non-metals, lying along the periodic table's staircase.
Atomic Structure & PeriodicityNeutron
An electrically neutral subatomic particle found in the nucleus, with a mass slightly greater than that of a proton.
Atomic Structure & PeriodicityNoble Gases
The group 18 elements, whose completely filled valence shells make them exceptionally unreactive.
Atomic Structure & PeriodicityNode
A region within an orbital where the probability of finding an electron falls to zero.
Atomic Structure & PeriodicityNucleus
The dense, positively charged core of an atom, containing virtually all of its mass in protons and neutrons.
Atomic Structure & Periodicityp-Block Elements
The elements of groups 13 to 18, in which the outermost electrons progressively fill p orbitals.
Atomic Structure & PeriodicityParamagnetism
Weak attraction into a magnetic field, shown by substances containing one or more unpaired electrons.
Atomic Structure & PeriodicityPauli Exclusion Principle
The rule that no two electrons in an atom may have the same set of all four quantum numbers.
Atomic Structure & PeriodicityPeriod
A horizontal row of the periodic table, corresponding to one principal quantum number of the valence shell.
Atomic Structure & PeriodicityPeriodic Law
The principle that the properties of the elements are periodic functions of their atomic numbers.
Atomic Structure & PeriodicityPeriodic Table
The tabular arrangement of the chemical elements by increasing atomic number, grouping those with similar properties in vertical columns.
Atomic Structure & PeriodicityPlum Pudding Model
J. J. Thomson's 1904 model picturing the atom as a sphere of diffuse positive charge with electrons embedded within it.