Chapter 1 Flashcards
Atomic number
Z, number of protons
Mass number
A, sum of protons and neutrons
isotopes
same atomic number, different masses (different number of neutrons)
atomic mass
equal to mass number in amu
atomic weight
weighted average of isotopes
mass of 1 mole in grams
avadagros number
1 mole, number of things
6.022 x 10 ^23
Rutherford
atoms have dense, positive nucleus
quanta
bundles of energy emitted as electromagnetic radiation from matter
energy of quanta equation
E= hf
h is constant= 6.626 x 10^ -34
Bohr
atoms is central protons with electrons in orbit
force is electrostatics between protons and electrons
angular momentum equation
L= nH/2pi
n is principal quantum number
energy of electron equation
E= -RH/ n squared
R= 2.18 x 10^-18 J/e
energy increases farther out from nucleus
atomic emission energy
E= hc/ wavelength
c= 3x 10 ^8
line spectrum
emit fluorescence when moving from excited to ground
Energy level tansition
E= Hc/ wavelength
= Rh (1/ni^2 - 1/nf^2
energy emitted is energy difference between initial and final energy
absorption spectra
from exciting electrons at specific wavelength
orbitals
electrons move rapidly around these regions of space
heisenberg uncertainty principle
cant determine electron momentum and position together
pauli exclusion
no 2 electrons can have same set of 4 quantum numbers
quantum numbers
n, l, ml, ms
principal quantum number
n, positive integer, larger means higher energy level and shell radius
max electrons in shell
2n squared
azimuthal quantum number
l, angular momentum, shape and number of subshells
from 0 to n-1
0=s 1=p 2=d 3=f
max number of electrons in subshell
4l +2
magnetic quantum number
ml, where electrons are likely found, orbital holds 2 electrons
from -l to l
s is sphere and p is dumbbell
spin quantum number
ms, - or + 1/2
orbitals have paired spin
configuration
pattern in which subshells are filled
first number is n
letter is subshell
superscript is number of electrons in subshell
afbau principle
electrons fill low to high energy subshell and fill completely before next
N+ L rule
shows rank of highest energy
hunds rule
fill orbitals to have max number of half filled orbitals with parallel spin
if all have full- its lower E and stable
exceptions to configurations
chromium has s1,d5
copper has s1 d10
paramagnetic
magnetic field causes parallel spins in unpaired electrons, causes align and attraction to magnetic field
diamagnetic
only paired electrons, slightly repelled by magnetic field
