chem things i keep forgetting

alpha decay

emission of 4/2 He

beta decay

neutron becomes a proton

positron emission

1/1 proton —> 1/0 neutron + beta+ particle

electron capture

proton absorbs e- and becomes a neutron

gamma decay

emission of energy

What species undergo alpha decay?

atomic number > 83

What species undergo beta decay?

n:p ratio high

What species undergo positron emission?

n:p low, light nuclei

What species undergo electron capture?

n:p low, heavy nuclei

What species undergo gamma decay?

most nuclear decays are gamma

If rate quadruples when concentration doubles…

the reaction is second order

If rate doubles when concentration doubles…

the reaction is first order

If the rate does not change when concentration is doubled…

the reaction is zeroth order

What is the order of this concentration vs time graph?

zeroth order

What is the order of this concentration vs time graph?

1st order

What is the order of this concentration vs time graph?

2nd order

What is this a linearization of?

zeroth order reaction

What is this a linearization of?

1st order reaction

What is this a linearization of?

2nd order reaction

microstate

a specific microscopic configuration of a system; more microstates = more entropy

delta S and qrev

delta S = qrev/T = delta H/T

standard/absolute entropy

the entropy value for the standard state of a species; standard state elements S=/= 0

How do you predict boiling point using ghost equation?

delta G = 0 so delta H =T * delta S

Keq = Q

equlibirum

Keq > Q

rxn will shift right

Keq < Q

rxn will shift left

strong acids

HClO_4, HClO_3, HBr, HCl, HI, HNO_3, H₂SO₄

strong bases

Ba(OH)_2, Ca(OH)_2, CsOH, LiOH, KOH, RbOH, NaOH, Sr(OH)₂

higher charge and smaller size makes…

a better Lewis acid

What kind of titration is this?

strong acid/strong base

What kind of titration is this?

strong base/strong acid

Titration at any point

ICF, divide by Vtot to find molarity if needed

Acid/Base dissociation equilibria

ICE

n AOs

= n MOs

sigma bonds

e- density on internuclear axis

pi bonds

e- density above and below internuclear axis

What crystalline cell is this?

face centered cubic; CN = 12

What crystalline cell is this?

base centered cubic; CN = 8

atomic/molecular solids

low BP/MP; van der Waals/LDF

network covalent solids

High BP/MP; covalent bonds

ionic solids

Highest BP/MP; electrostatic attraction

metallic solids

metallic bonding

for complexes: Kf > Q

shift R; soluble

for complexes: Kf < Q

shift left; insoluble

field splitting energy…

is in Joules/photon

unpaired d shell e-…

means the complex is colored and influenced by a magnetic field

m = ItM/nF

mass plated = current x time x molarity / # of e- x Faraday’s constant

arrhenius acid

acid that increases the H+ concentration of a solution

lewis acid

acid that accepts lone pairs of electrons

bronsted-lowry acid

acid that dissolves and releases protons

nuclear activity

activity = initial activity x (0.5)^(t/t1/2)