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Atomic mass VS Atomic Weight: - 🧠ANSWER ✔✔-atomic mass=mass
number (p+n)
-atomic weight=weighted average of natural isotopes
-isotopes=n# and mass varies (extreme isotopes are rarely found coz they
decay fast)
-ex. H1(protium), H2 (deuterium), H3(tritium)
*period table lists avg weight not Σmass of isotopes
*H- =hydride ion not isotope!
,atomic symbol: - 🧠ANSWER ✔✔Superscript=mass#, MASS of N+P
Subscript=atomic#, atomic protons
Weight=avg of isotopes
charge=indicates -/+ electrons
*1proton or 1neutron=1amu
4 fancy names of quantum number: - 🧠ANSWER ✔✔1. Principal (energy lv)
2. azimuthal/angular= shape from -0 sphere,
-1 p-dumbbells,
-2 d-clover,
-3 F-snowflake
3. magnetic (orientation)
4. spin (clockwise/counterclock)
Rutherford, Plank, Bohr contribution: - 🧠ANSWER ✔✔a. Rutherford=α-
particle deflected off Au foil>found (+) nucleus>debunk plum pudding
, b. Planck=energy levels exist as discrete quantum's; e- cannot be infinitely
anywhere
c. Bohr=dense positive nucleus surrounded by e- orbits with discrete
energy lvs
Quantum model: - 🧠ANSWER ✔✔a. electrons localized in orbitals not
"glued" there
b. orbitals=regions of space with increase e- probability NOT defined paths
c. Heisenberg uncertainty principle=impossible to know both electron
position & momentum at same time (when it's moving u can't get accurate
position vice versa)
d. to locate a e- you need to know it's (N, L, mL, mS)
atomic absorption spectrum: - 🧠ANSWER ✔✔-each element has unique
light absorption spectrum (used as element's fingerprint/ID)
-pattern of light emission represent electron's energy transition
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