isoelectronic: same electron config (ex: F- & Ne)
Config for anions (move to RIGHT x spaces), cations (move to LEFT x spaces)
*****Transition Metals will lose its valence S electrons before losing and d electrons, so GET RID OF LAST "4S e's" AND PUT THEM IN THE LAST D ORBITAL!!!!!!!!!! (Even though 4s should be lower energy than 3d...TM's more stable with unfilled 4s and quasi-filled 3d orbital, rather than fillied 4s orbital...)
"I dont think there is a hard rule for transition metals which makes it a lot trickier. Some of them have d orbitals that are degenerate with the 4s orbital (same energy level). In some cases, it is better to have all half filled orbitals like 3d5 via Hund's rule. Supposedly this makes it more stable than say 4s2 3d3 and this explains why some orbitals can lose 4s electons before 3d ones even though 4s is lower in energy. Others can be different where the 3d orbital is at a higher energy level than the 4s orbitals."
diamagnetic: all of its e's (even # or all e-'s PAIRED) spin-paired, NO net magnetic field, REPELLED by a magnetic field
paramagnetic: all of its e's (odd-numbered or some e-'s UNPAIRED) are NOT spin-paired, ATTRACTED to a magnetic field
atomic emission spectrum: light emitted when when an atom's electrons FALL to their ground states
atomic absorption spectrum: light absorbed when an atom's electrons are EXCITED to higher energy levels
"Bohr atom" has only 1 electron...so count scenarios properly (Model for the Hydrogen atom)
In balancing ADDITION of alpha particle, balance out equation of mass and atomic numbers with this:
Alpha decay: Reduces the parent’s atomic number by 2 and mass number by 4 (releases an alpha particle = HELIUM atom: 2 protons and 2 neutrons). Any element with atomic number greater than 83 will automatically undergo alpha decay and start releasing protons/neutrons in the form of alpha particles.
- Decreases the number of neutrons AND protons in large nucleus
Beta decay: Neutron decomposes into a Proton (and Electron), or vice versa via weak nuclear force
http://www.youtube.com/watch?v=1j-eDPLSBm0
*Mass number stays the same!!
- β- à TOO MANY neutrons
o Increases the number of protons
- ex: Carbon 12 vs. Carbon 14... Carbon 14 gains a P+, releases an E-
- β+ à TOO FEW neutrons
o Decreases the number of protons
Electron Capture: Converts protons into neutrons
- nucleus draws in inner-shell electron, P and E react to form a Neutron
*Mass number stays the same, only Atomic number changes!! (ex: Rb to Kr)
http://www.youtube.com/watch?v=mhhAXQ5euYw- Decreases number of protons, porque hay demasiado!
Gamma decay: Simply the expulsion of energy. Does not change the identity of the nucleus. Gamma photons emitted so atom can relax to its ground state.
- Gamma rays are emitted by the nucleus! and are often used in medicine to KILL CELLS
http://www.mcatquestion.com/findquestion.php?arg1=1044
one of like a trillion HALF-LIFE EQUATIONS:
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