chem unit 4 + final exam

work=

Fxd or PdeltaV

qsurroundings=

-qsystem

1 L x atm

101.3J

state function

only depends on current, not past properties of a system (total energy and enthalpy)

path functions

heat and work

delta h=

products-reactants

w>0 when

ideal gas compressed

mass of subatomic particles

mass: electron<proton<neutron

average atomic mass

weighted average mass of one atom of an element based on natural abundance of isotopes

average molar mass

the mass of one mole of a substance (6.022e23 particles)

de broglie equation

wavelength=h/mv

electromagnetic spectrum in order of increasing frequency

radio<microwaves<infrared<visible<UV<x rays<gamma rays

photoelectric effect

photon has an energy based on frequency, increasing intensity increases number of electrons, not their energy

structural isomer (constitutional isomer)

differ in how the atoms are connected to each other

spatial isomer (stereoisomer)

relative orientations of atoms in space are different

enantiometers

mirror images

diastereomers

not mirror images

cis isomer

same side

trans isomer

opposite sides

homonuclear

atoms made of one element

two electron sets

linear, 180 degrees

three electron sets

trigonal planar, 120 degrees

three electron sets, 1 is a lone pair

bent, <120 degrees

four electron sets

tetrahedral, 109.5 degrees

four electron sets, 1 is a lone pair

trigonal pyramidal, <109

four electron sets, 2 are lone pairs

bent, «109

five electron sets

trigonal bipyramidal, 90 and 120 degrees

five electron sets, 1 is a lone pair

seesaw, 90, 180, 120 degrees

five electron sets, 2 are lone pairs

T-shape, 90 and 180 degrees

five electron sets, 3 are lone pairs

linear, 180 degrees

six electron sets

octahedral, 90 degrees

six electron sets, 1 is a lone pair

square pyramidal, 90 degrees

six electrons sets, 2 lone pairs

square planar, 90 degrees

Molarity (M)

moles solute/ Liters solution

molality (m)

moles solute/ kg solvent

mole fraction (x)

moles solute/ total moles solution

wt%

mass solute/ mass solution x100

vol%

volume solute/ volume solution x100

ppm

mass solute/ mass solution x10^6

ppb

mass solute/ mass solution x10^9

pure water at 4 degrees C

1L=1kg

1ppm=1mg/L

1ppb=1microgram/L

always soluble

alkalai metals, ammonium, NO3-, ClO3-, ClO4-, C2H3O2-

soluble except Ag+, Pb2+, Hg2+

Cl-, Br-, I-

sulfate solubility exceptions

Ag+, Ca2+, Ba2+, Pb2+, Hg2+

ammonium

NH4+

hydroxide

OH-

carbonate

CO3^2-

nitrate

NO3^-

phosphate

PO4^-3

acetate

C2H3O2^-

perchlorate

ClO4^-

sulfate

SO4^-2

strong bases (soluble)

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

strong acids

HCl, H2SO4, HNO3, HBr, HI, HClO4, HClO3

aufbau

electrons fill lowest energy level first

hund’s rule

electrons first occupy each orbital singly with parallel spins

pauli exclusion principle

no two electrons can have the same set of quantum numbers