chapter 6/7 review Flashcards
waves
a disturbance that transmits energy through space
the longer the wavelength
the lower the frequency
the shorter the wavelength
the higher the frequency
the speed of light (c)
2.998x10^8 m/s
speed=
frequency times wavelenth
wavelength (λ) is measured in___
frequency (v) is measured in ___
λ= meters (m)
v= hertz (Hz)/ inverse seconds
frequency (V)
the number of waves passing a point in a given amount of time
EM spectrum pneunonic
Red Men Interview Very Ugly Xylophone Guys
EM spectrum longest wavelength to shortest wavelength
radio, microwaves, infrared, visible, ultra-violet, x-rays, gamma rays
constructive interference
when two like waves combine to create a larger wave
destructive interference
when two unlike waves combine to create no wave (flat line)
diffraction
a change in the direction of waves as they pass through an opening or around a barrier in their path
refraction
bending of waves as they pass from one medium to another
photon
a particle of light
C=
λV
what were the main issues of classical physics
experimental data did not agree with theory, had to change theory
blackbody radiation, photoelectric effect, atomic emission spectra
blackbody radiation
energy like matter is discontinuous or quantized
the quantum EM radiation is proportional to the frequency of the radiation
Energy=
h times V
planks constant
6.626x10^-34 Js
photoelectric effect
when light strikes a metal, electrons are emitted
emission only occurs at certain threshold frequencies
atomic emission spectra
when an electron is struck with energy, it is excited and emits light
bohr model of the atom
-electrons move around the nucleus in a set of circular orbits
-as long as an electron stays in its given orbit, not energy is emitted, with a fixed radius and energy
-an atom emits energy as a photon when the electron FALLS from to an orbit with a SMALLER radius and LOWER energy
E (with wavelength)
hc/λ
ground state
lowest energy level
n=1
excited state
electron moves out of the ground state into a state with a HIGHER n value
when an electron falls from an excited state to a lower energy level,
it emits a photon
increasing atomic number (Z) results in
a greater effective charge
λ (Broglie wavelength)=
h/p or h/ mass times speed/velocity
you can never know the exact ___ and ____, you will either know one or another
position or momentum
types quantum numbers
n= the principle quantum number
l= the orbital angular momentum quantum number
ml= angular momentum quantum number
ms= electron spin quantum number
n (principle quantum number) describes and accepted values
the shell where the electron is located
n can have positive, whole-number values, non-zero
ex) 1,2,3,4…
all electrons with the same value of n are in the same
principle electron shell or level
l (angular momentum) describes and its accepted values
describes the SHAPE of the orbital where the electron is located
describes the subshell where the electron is located
can have zero, and positive whole-number values
ex) 0,1,2,3…
it CANNOT be the same value as n, has to be at least 1 lower!!!
subshells of l
l=0, s
l=1, p
l=2, d
l=3, f
ml (magnetic quantum number) is described and accepted values are
describes the orientation of the orbital where the electron is located
can have negative, zero, and whole-number values from -l to +l
m,=-1,0,1
ms (spin quantum number)
describes the orientation of the electron spin
can have +1/2 or -1/2 values only
orbitals
where electrons are likely to be found around the nucleus
the number of l values in a subshell is equal to
the number of allowed ml values (2l+1)
s orbitals have a ___ shape (l=0)
spherical shape
p orbitals have a ___ shape (l=1)
two lobes with a node where e- cannot go
d orbitals have a ___ shape (l=2)
multiple lobes and nodes
f orbitals
l=3
an electron with higher principle quantum energy level will
generally be higher in energy
in a single atom, subshells with the same
principle number are DEGENERATE
in a multi-electron atom, sublevels with the same principle energy level are
no longer degenerate
electrons close to the nucleus ____ causing them to have a LOWER____ and a HIGHER_____
-SHEILD electrons farther out from the nucleus
-effective nuclear charge (zeff)
-energy
Pauli exclusion principle
no two electrons can have the same quantum numbers
afabu principle
electrons fill lower energy orbitals first
hunds rule
when multiple degenerate orbitals are available, electrons fill each singly before paring with parallel spins
orbitals with the same __ and ___ are degenerate
n and l
effective nuclear charge
increases across the periodic table due to shielding
zeff= Z- S (number of protons minus number of core electrons)
valance electrons
electrons in the outermost shell
exceptions to electron configuration filling
chromium, molybdenum, copper, silver, and gold
paramagnetic
unpaired e-
diamagnetic
no unpaired e-
ionization energy
the amount of energy required to remove an electron from a neutral atom in its gas phase
always ENDOTHERMIC
ionization trend plus exceptions
increases from the left to the righter and up the periodic table
exceptions: group 2 and 13 switch and group 15 and 16 switch
electron attachment enthalpy
the change when a gaseous atom adds an electron, forming a gaseous anion
X(g) + e- —> X-(g)
EXOTHERMIC and negative
electron affinity
energy required to detach an electron from an anion with a negative 1 charge
X-(g) —> X(g) + e-
positive and ENDOTHERMIC
electron affinity and attachment trend plus exceptions
increases favorability from the left to right and up the periodic table
exceptions: row 2 (less favorable) and 3 switch
noble gases very unfavorable
groups 1 and 2 switch and groups 15 and 14 switch
atomic radius and trend
measure of the size of an atom
increases from the right to left and down the periodic table
ionic radius:
cations:
anions:
cations=smaller
anions= larger
electronegativity and trend
measure of the ability of an atom to attract electrons to itself
increases from the left to right and up the periodic table
noble gases excluded
francium is least EN and fluorine is most EN
