GChem: Atomic structure and periodic trends Flashcards
Bohr model, quantized energy states
Is there greater E jump from n=1 to n=2 or n=2 to n=3?
n=1 to n=2
The energies of discrete energy levels were given by Bohr in the following equation
En = (-2.178 *10^-18J)/n^2
n represents energy levels of the electron
Using Bohr’s model and different discrete energy levels, how can we calculate wavelength of photos emitted?
For this topic we need to think about how ____ and ____ have an inverse relationship according to a certain physics equation…
Subtract initial energy level of electron from the final energy of the electron
change in E is negative indicates that E is being released as electron falls to ground state, if change in E pos that means E absorbed by the electron
Then one can plug into the equation
Change in E = h(c/lambda)
plank’s constant h = 6.63 * 10^-34 J*s
c is the speed of light -> c = 3x10^8 m/s
What is a Bohr atom?
One that contains only one electron
example of atom that is NOT BOHR ATOM = H+ because it has pos charge from losing the one electron and now has no electrons at all
Is spectroscopy a form of separation?
NO
Diamagnetic
all electrons spin-paired so even number of electrons
Such an atom would be repelled by an externally produced magnetic field
Paramagnetic
When an atom’s electrons are not all spin-paired
Attracted into externally produced magnetic fields
If you ever need to write the electron configuration for an element in the d block…
for the f block…
for d, subtract 1 from n
for f, subtract 2 from n
Which elements have that weird d orbital electron configuration rule?
Cr, Mo
Cu, Ag, Au
Isoelectric
having the same numbers of electrons or the same electronic structure
Ex. If F gains an electron, it has the same electron configuration at Ne
Electrons that are ionized from transition metals come from…
the s orbital before the d orbital
Electron configuration of Ta
Pr?
4f14 5d3 6s2
[Xe]6s24f44
Where are the alkaline earth metals, alkali metals, halogens, rare earth metals in periodic table?
alkaline earth metals - Second group
alkali metals - First group
halogens - Second to last group
rare earth metals - F block
Electron affinity
and trend
Energy associated with the addition of an electron
If energy is released when electron is added, then EA is negative, but if energy is required in order to add the electron, the electron affinity is positive (When atom has closed shell OR subshell)
Halogens has a large negative EA bc they get the desired octet
Electron affinities generally become more neg across a period left to right (exception is noble gases and other anomalies)
Electronegativity
What is it? What is the trend?
List the highest EN atoms
Atom’s ability to pull electrons to itself when if forms a covalent bond
The greater this tendency to attract electrons, the greater the atom’s electronegativity
Electronegativity basically behaves like ionization energy
Increases diagonally up across the periodic table
F>O>N = Cl >Br >I> S> C=H
Fonclibrisch