Ch.7 Review Flashcards
(34 cards)
Electromagnetic Spectrum?
(Increasing energy/decreasing wavelength)
Gamma Rays , X-rays , UV rays, Visible (VIGBOYR) , Infrared , Microwaves, Radios
Electromagnetic radiation?
Ways that energy travels through space
Planck?
Energy is quantized & can occur in discrete units of size (small “packets” of energy = quantum)
(D E) = (planck’s constant(h)) (frequency)
Albert Einstein?
Electromagnetic radiation quantized. Electromagnetic radiation is a stream of particles called photons.
Ephoton = hv
Photocleric Effect?
Study in which the frequency of light was varied to show that no electrons are emitted by a given metal below a specific threshold. But for light with frequency greater than threshold number of electrons emitted increased with increased frequency.
Einstein “energy has…”?
Energy has mass. Special theory of relativity.
m= (E)/ (c^2)
Energy of photon?
Ephoton = (hc)/ (wavelength)
Dual nature of light?
Light has both wave-like and particle-like properties.
Louis de Brogile?
Particles have wavelike properties.
(wavelength) =(h)/ (mv)
v= velocity
Diffraction?
Light is scattered from a regular array of points or lines. Showed that particles (like electrons) have wavelengths.
Emission spectrum?
When H2 receives energy and some H-H bonds break resulting in H atoms becoming excited and releasing this energy by emitting light of various wavelengths.
Line Spectrum? Significance?
Hydrogen emission spectrum. Significant because it shows that only certain energies are allowed for the electrons in hydrogen atom. So electron energy in H is quantized.
Bohr?
Electrons in a hydrogen atom move around the nucleus only in certain allowed orbitals.
Energy level available to the electron in the hydrogen atom?
E = (-2.178 X 10^-18)J(z^2/n^2)
z-nucleur charge
n-orbit radius
Important things about Bohr’s model?
Model correctly fits quantized energy of hydrogen atom & postulates only allow certain circular orbitals.
As electrons become more tightly bond energy becomes more neg. because it releases energy.
Energy Change in H equation?
DE = (-2.178 x 10^ -18) (1/ nfinal^2)-(1/n initial ^2)
Energy required to remove an electron from a hydrogen atom in its ground state?
N final = infinity so
energy required = 2.178 x 10^ -18
de Brogile?
Electrons show wave properties.
Shroedinger and Shroedinger’s equation?
Electrons are bound to nucleus seem to be a standing wave. Wave functions = orbitals. Can calculate allowed orbitals using Shroedinger’s equation.
Heisenberg’s uncertainty principle?
There is a fundamental limitation to just how precisely we can now both the position and momentum of a particle at a given time.
Atomic orbitals?
Square of function. Just an electron density map (probability) .
Principle quantum number?
n . Givens size and energy of orbital. Greater than 0.
Angular momentum quantum number?
l . 0-> (n-1) . 0= s , 1=p , 2= d , 3=f, 4=g .
Magnetic quantum number?
ml . Relative orientation of orbital in space.
