Light, Electromagnetic Spectrum, and Quantum Atomic Model Flashcards

Vocabulary practice flashcards based on the lecture covering wave properties, atomic spectrum models, quantum mechanics, and quantum numbers.

Wavelength ($\lambda$)

The distance between two successive wave peaks, expressed in units of length ($m$).

Frequency ($\nu$)

The number of wave peaks that pass a given point per unit time, measured in cycles per second or $s^{-1}$ ($Hz$).

Amplitude

The height of a wave peak measured from the baseline.

Wave Number ($\nu$)

The number of waves in a given distance, expressed in units of $1/cm$ ($cm^{-1}$).

Photon

A discrete packet or quantum of energy in an electromagnetic field, coined to describe visible-light particles.

Planck's Constant ($h$)

A physical constant equal to $6.62607004 \times 10^{-34}\,m^2\,kg/s$ (or $Js$), used to calculate photon energy ($E = h \times \nu$).

Monochromatic Radiation

Electromagnetic radiation composed of only one wavelength.

Continuous Radiation

Electromagnetic radiation that spans a whole continuous array of different wavelengths without dark spots.

Absorption Spectrum

A spectrum produced when a continuum of radiation passes through unexcited atoms, which absorb specific wavelengths and leave dark spaces in the continuous spectrum.

Emission Spectrum

A line spectrum produced when energetically excited atoms emit light at specific quantized wavelengths.

Plum Pudding Model

Atomic model produced by J.J. Thomson in 1904 depicting electrons scattered throughout a spherical cloud of positive charge.

Planetary Model

Atomic model proposed by Niels Bohr in 1913 in which electrons move around the nucleus in fixed circular orbits with quantized energy levels.

Rydberg Constant ($R_H$)

A constant equal to $2.18 \times 10^{-18}\,J$, used in calculating the quantized energy of hydrogen electron orbits ($E_n = -R_H \left(\frac{1}{n^2}\right)$).

de Broglie Wavelength

The wavelength associated with a moving particle of mass $m$ and velocity $v$, given by $\lambda = \frac{h}{mv}$.

Heisenberg's Uncertainty Principle

The principle stating that on the mass scale of atomic particles, the exact position, direction of motion, and speed cannot be determined simultaneously.

Wave Function ($\psi$)

A mathematical term derived from Schrödinger's wave equation that defines the shape of an atomic orbital.

Electron Density ($\psi^2$)

The square of the wave function ($\psi^2$), which represents the probability of finding an electron in a given region of an atom.

Principal Quantum Number ($n$)

The quantum number ($n = 1, 2, 3, \dots$) that specifies the main electron shell and size of the orbital.

Angular-Momentum Quantum Number ($l$)

Also called the subshell quantum number ($l = 0, 1, 2, \dots, n-1$); specifies the subshell shape ($s, p, d, f$).

Magnetic Quantum Number ($m_l$)

The quantum number ($m_l = -l, \dots, 0, \dots, +l$) that specifies the 3D orientation of an orbital in space.

Spin Quantum Number ($m_s$)

The quantum number that designates the spin orientation of an electron, taking values of $+\frac{1}{2}$ or $-\frac{1}{2}$.

Node

A region in space within an orbital where the probability of finding an electron is zero ($\psi^2 = 0$).

Effective Nuclear Charge ($Z_{eff}$)

The net positive charge experienced by an electron in a multielectron atom, taking into account the screening effect ($S$) of inner core electrons.

Degenerate Orbitals

Orbitals that share the exact same energy level.