general chemistry (1-3 may 18th) Flashcards
atomic mass vs atomic weight
atomic mass is nearly synonomous with the mass number - sum of protons and neutrons
atomic weight is the weighted average of the atomic masses
plancks and Bohrs energy calculations
E=hc/lamda = RH (1/ni2 - 1/nf2)
Heisenberg uncertainity principle
it is impossible to determine with perfect accuracy the momentum and position of an electron, because of trying to do the two measurements at the same time
maximum number of electrons within a shell
2n^2
l quantum number
Angular momentum, describes the shape and number of subshells at the given energy level
l=0 is s
l=1 is p
l=2 is d
l=3 is f
magnetic quantum number
tells u the specific orbital within a subshell that the electron is
possible values are integers -l to l, including zero
ex:
2p
l= 1
so -1, 0, 1 —> px, py,pz
spin quantum number
ms, +1/2 or -1/2
configuration for anions
just fill up orbitals in configuration
configuration for cations
make to remove electrons from the highest n first,
ex: Fe 3+, remove electrons from 4s before 4d
hunds rule
-subshells filled to have the max number of half-filled electrons with parallel spins
-half filled and fully-filled orbitals have higher stability than other states
chromium configuration
special bc you move one out of s to have more half filled orbitals
[Ar]4s13d5
paramagnetic
if they have ANY unpaired electrons, they are attracted to a magnetic field
diamagnetic
only paired electrons, will be slightly repelled by a magnetic field
valence electrons for transition elements
those in the highest s and d subshell
valence electrons for lathinide and actinine
those in highest s and f subshells
metals characteristics
lustrous, high melting points, malleability, ductility, high electropositivity
transition metals
-electrons can move around- good conductors because of loose hold on electrons of the d orbitals
-forms hydration complex with water and nonmetals,
nonmetals
dull, poor conductors, brittle
metalloids
characteristics of both metals and nonmetals, staircase
Zeff
effective nuclear charge, net positive charge experienced by electrons in the valence shell
-INCREASES LEFT TO RIGHT (more protons), little change in a group HOWEVER, valence electrons become increasingly separated as u move down a group
atomic radius
Decreases left to right and up (think fluorine is small)
Ionic radius (which is smaller and bigger?)
- cations smaller, anions larger
key examples for exceptions to the octet rule
incomplete: boron: 2
expanded: phosphorus (10), sulfur (12), chlorine (14) - bc of d orbitals
lewis acid
any compound that will accept a lone pair of electrons
