25.5 Atomic Structure Flashcards
emission spectrum
unique energetic fingerprint of an atom
Ephoton equation (2)
1) Ephoton = h f
2) Ephoton = h (c/λ)
what does the bohr model predict for an emission spectra?
elements will have a line emission spectra instead of a continuous spectra
=> only photons with certain energies will be absorbed or released
Bohr atom
atom with only 1 electron
how does the distance between energy levels change as you increase n?
distance between energy levels DECREASE with increasing n
what does a positive or negative ΔEn indicate?
\+ΔEn = E absorbed (photon absorbed, electron jumps) -ΔEn = E released (photon emitted, electron falls)
quantization
electrons held by an atom only exist at discrete energy levels
how does an electron in a higher energy shell compared to one in a lower energy shell
1) higher energy in higher energy shell
2) farther distance from nucleus in higher energy shell
orbital
3D region around nucleus in which electron is most likely to be found
subshells
complex orbital shapes that describe the most probable regions an electron will occupy (four types exist: s, p, d, f)
what happens as you increase the number of energy shells
gain one more subshell (s -> p -> d -> f)
how many spin sates can an electron have?
2 (an orbital can occupy one up, one down)
electron configuration basic principles (3)
1) Aufbau principle
2) Hund’s rule
3) Pauli exclusion principle
Aufbau principle
electrons occupy lowest E orbitals first
Hund’s rule
electrons in same subshell occupy availabale orbitals singly first
Pauli exclusion principle
only two electrons in any orbital
s subshell (# of orbital orientations, max # electrons)
1 orbital orientations
2 electrons
p subshell (# of orbital orientations, max # electrons)
3 orbital orientations
6 electrons
d subshell (# of orbital orientations, max # electrons)
5 orbital orientations
10 electrons
f subshell (# of orbital orientations, max # electrons)
7 orbital orientations
14 electrons
noble gases
elements that have all subshells in outermost electron shell filled (full octets)
diamagnetic atoms
atoms with all electrons spin-paired
paramagnetic atoms
atoms where not all electrons spin-paired
diamagnetic atom properties (3)
1) even # of electrons
2) all occupied subshells are filled
3) not attracted to external magnetic field
paramagnetic atom properties (2)
1) NOT all occupied subshells are filled
2) attracted to external magnetic field
can paramagnetic atoms have even # of electrons
yes (can be even or odd)
=> odd # electrons is definitely paramagnetic though
what does the block an atom is in indicate?
block name = highest-energy subshell that contains an electron
what is often used as starting points for writing out the electron configurations of an atom?
[noble gases]
d block exception
subtract 1 from period #
f block exception
subtract 2 from period #
what are the anomalous electron configuarion atoms?
Atoms in the Cr and Cu families
- have nd(4) or nd(9) as highest occupied E subshell, so will take one from the previous s subshell to fill up d orbitals
isoelectronic atoms
atoms/ions of different elements but have the same electron configuration
what electrons are ionized from an atom first?
the valence shell (highest energy orbital) ]
=> except for transition metals: ionize the s orbital electrons, then lose d electrons
excited atom
different electron configuration, but will still have same number of electrons (just an electron jumps up to higher level unexpectedly)
