CHEM 18 1st DEPARTAMENTAL EXAM Flashcards
periodic oscillation by which energy is transmitted through space.
wave
the distance between two corresponding points in a wave—between the midpoints of two peaks or two troughs
Wavelength (λ)
number of oscillations that pass a
particular point in a given period of time.
frequency (ν)
defined as half the peak-to-trough height
amplitude
- distance traveled by a wave per unit time
- measured in meters per second (m/s)
speed (v)
energy that is transmitted, or radiated, through space in the form of periodic oscillations of electric and magnetic fields
Electromagnetic radiation
- contradict the theories of classical physics
- electromagnetic radiation whose wavelength and color that depends on the temperature of the object
blackbody radiation
classical physics could not explain the sharp decrease in the intensity of radiation emitted at shorter wavelengthswhich was referred to as _______________
ultraviolet catastrophe
explained the ultraviolet catastrophe by proposing that the energy of electromagnetic waves is quantized rather than continuous.
Max Planck
(A phenomenon in which electrons are ejected from the surface of a metal that has been exposed to light).
photoelectric effect
(a principle that matter and energy have properties typical of both waves and particles
wave–particle duality
states that the uncertainty in the position of a particle (Δx) multiplied by the uncertainty in its momentum (Δ[mv]) is greater than or equal to Planck’s constant divided by 4π:
Heisenberg uncertainty
developed wave mechanics
Erwin Schrödinger
mathematical technique that describes the relationship between the motion of a particle that exhibits wavelike properties (such as an electron) and its allowed energies
wave mechanics,
three quantum numbers
n, l, and ml
tells the average relative distance of an electron from the nucleus:
n = 1, 2, 3, 4, …
principal quantum number
- second quantum number
- describes the shape of the region of space occupied by the electron
azimuthal quantum number (l).
- third quantum number
- describes the orientation of the region in space occupied by an electron with respect to an applied magnetic field
magnetic quantum number (ml)
Each wavefunction with an allowed combination of n, l, and ml values describes an
atomic orbital
the number of protons in the nucleus
nuclear charge Z
No two electrons in an atom can have the same values of all four quantum numbers (n, l, ml, ms).
Pauli exclusion principle:
The electron moves around the nucleus in circular orbits that can have only certain allowed radii.
Bohr’s Model
