Knowt 6 - Electric Structure & Periodic Properties

Amplitude

Extent of displacement caused by a wave

Electromagnetic radiation

Energy transmitted by waves with electric and magnetic components

Electromagnetic spectrum

Range of energies from radio to gamma rays

Frequency (ν)

Number of wave cycles per unit time

Hertz (Hz)

Unit of frequency as cycles per second

Intensity

Wave energy property related to amplitude, like brightness or loudness

Interference pattern

Alternating bright and dark fringes from wave interference

Line spectrum

Discrete wavelengths emitted by excited atoms

Photon

Smallest packet of electromagnetic radiation, a light particle

Wave

Oscillation transporting energy over time or space

Wavelength (λ)

Distance between consecutive wave peaks or troughs

Excited state

Energy level higher than the ground state

Ground state

Lowest possible energy state for electrons

Atomic orbital

Mathematical function describing electron behavior in an atom

Electron density

Probability of finding an electron in a region, squared wavefunction value

Heisenberg uncertainty principle

Impossible to know both position and momentum exactly

Node

Point of zero amplitude in a standing wave

Orbital diagram

Box representation of electron configuration

Quantization

Restriction of properties to discrete values

Quantum mechanics

Study of matter using quantization, wave-particle duality, and uncertainty

Quantum number

Specific value characterizing electron arrangement

Standing wave

Localized wave with discrete wavelengths from boundary conditions

Wave-particle duality

Particles exhibit both wave and particle properties

Aufbau principle

Electron configuration built by adding electrons to subshells in atomic number order

Core electron

Electron in inner shells

Degenerate orbitals

Orbitals with the same energy

Electron configuration

Listing of electron occupancy in shells and subshells

s orbital

Spherical region for l=0 orbitals

p orbital

Dumbbell-shaped region for l=1 orbitals

d orbital

Four-lobed or dumbbell-torus region for l=2 orbitals

f orbital

Multilobed region for l=3 orbitals

Hund’s rule

Single electrons occupy subshell orbitals before pairing, with same spin

Principal quantum number (n)

Number specifying electron shell

Secondary (angular momentum) quantum number (l)

mber distinguishing orbital shapes

Magnetic quantum number (ml)

Number indicating orbital orientation

Spin quantum number (ms)

Number for electron spin direction (+1/2 or -1/2)

Pauli exclusion principle

No two electrons share all four quantum numbers

Shell

Orbitals with the same principal quantum number

Subshell

Orbitals with same n and l values

Valence electrons

Electrons in outer shells

Valence shell

High-energy outer shells

Covalent radius

Half the distance between nuclei of bonded identical atoms

Electron affinity

Energy change from adding an electron to a gaseous atom or ion

Ionization energy

Energy to remove an electron from a gaseous atom or ion

Isoelectronic

Atoms or ions with identical electron configurations

Speed of Light Constant

c = 2.998 × 10⁸ m/s

Planck’s Constant

h = 6.626 × 10^-34 J∙s

Speed of Light Equation

c = λν

Planck’s Energy Equation

E = hν

Heisenberg’s Uncertainty Principle Equation

∆x ∙ ∆p_x ≥ h/4π