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| -yawn- i'm lazy to write any more stuff... i mean i already did 10 out
of 22 chapters! (roughly condensed notes of around 300 pages)
maybe if i find an interesting topic, i'll write up some notes for it.
or if anyone emails me or something. lol or if i cram for finals again.
cya around!
-thetomatohead :)
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| Chapter 10: Physical characteristics of gases
10-1 kinetic molecular theory of matter
10-2 pressure
10-3 gas laws
10-1
kinetic molecular theory: particles of matter are always in motion
ideal gas: imaginary gas that fits all assumption of kinetic molecular theory
-gas
particles made of tiny articles that are far apart relative to size
(gas
particles occupy volume 1000x greater than solid/liquid particles)
-collisions
between gas particles/container walls are elastic (no net loss of
kinetic
E) [[as long as temperture is constant]]
-no forces of attraction/repulsion between gas particles
- avg. kinetic E of gas particles depends on temp. of gas
Kinetic Energy= 1 (mass)(velocity)^2
2
All gases at the same temperature have same average kinetic energy. ex: He gas particles move faster than Neon gas particles b/c they are lighter.
-expansion: no definite shape or volume
-fluidity:
attractive forces are relatively insignificant so gas particles are
able to glide past -each other easily (fluids)
-low density: 1/1000 of same substance in solid/liquid form because particles are far apart
-compressibility: initally gas particles very far apart but then become crowded
-diffusion: mixing of particles of 2 substances caused by random motion
3 factors of gas particles affect rate of diffusion:
1. speed of gas particles
2. diameters
3. attractive forces between them
-effusion: gas under pressure let out through an opening. rate of effusion directly proportional to velocity
10-2
pressure: force/area
barometer: measures atmospheric pressure
unit
symbol def.
Pascal
Pa SI
pressure unit 1 Pa= 1 N (newton)/m^2 (meters squared)
atmosphere atm 1 atm= 760 mmHg
= 760 torr
= 1.01325 X 10^5 Pa
= 101.325 kPa
10-3
STP: 1 atm, 0 C (273.15 K)
absolute zero: -273.15 C (0 K) lowest temp possible
gas laws
Boyle: P1V1=P2V2 (Boyle is a PerV)
Charles: V1 = V2 (Charles likes to watch T V [switch around])
T1 T2
Gay Lussac: P1 = P2 (Gay Lussac likes to ParTy)
T1 T2
combined: P1V1 = P2V2 (PerVs drink Tea)
T1
T2
Dalton's law partial pressure: P [total] = P1 + P2 + P3 ....
P [atm] = P [gas] +
P [water]
ideal gas law: PV=nRT (PiVNeRT)
Chapter 9: Stoichiometry
9-1 introduction to stoichiometry
9-2 ideal stoichiometric calculations
9-3 limiting reactants and percent yield
9-1
composition stoichiometry: mass relationship of elements in compounds
rxn stoichiometry: masss relationship between reactants/products in a chemical rxn
mole ratio: related amount of moles of any 2 substances in a chemical rxn
9-2
amount of given substance (in mole) X mole ratio(mol unknown over moles given) = amount of unknown (in mole)
amount of given substance (mol) X mole ratio X molar mass of unknown (g/mol)=amount of unknown substance (in g)
9-3
limiting reactant(reagent):
reactant thats used up first in a rxn. reactant that limits amount of
other reactants that can combine and the amount of product that can form
-reactant with the lowest mole/coefficient ratio
excess reactant: substance not completely used up in a rxn
theoretical yield: max. amount of product that can be produced from a given amount of reactant
actual yield: the measure amount of product obtained from a rxn
percent yield:
actual yield X 100
theoretical yield
Chapter 8: Chemical Equations and Reactions
8-1 describing chemical rxns
8-2 types of chemical rxns
8-1
chemical equation: represents relative amounts of reactants/products in a chemical rxn using symbols and formulas
indications of chemical rxns
-change that releases heat and ligh
-production of a gas
-formation of a precipitate (a solid produced from a chemical rxn in a solution)
formula equation: represents reactants/products of a chemical rxn using symbols or formulas
8-2
synthesis (composition) rxn: 2 or more substances combine to form new compound
X+ Y ---> XY
X, Y can be elements/compounds
Group 1-Halogen
MX
Group 2-Halogen
MX2
decomposition: single compound undergoes rxn to produce 2 or more simpler substances
XY --> X + Y
XY is compound. X, Y can be elements/compounds
electrolysis: decomposition of substance by an electric current
decomposition of metal carbonates
metal carbonate --> metal oxide + CO2
decomposition of metal hydroxides
metal hydroxide (except those w/ Gr. 1 metals)--> metal oxide + H2O
decomposition of metal chlorates
metal chlorate ------> metal chloride + O2
decomposition of acids
(certain) acids ----> nonmetal oxides + H2O
single replacement (displacement) rxn: one element replaces a similar element in a compound
A + BX ---> AX + B [AX, BX, BY-Compounds]
Y + BX ---> BY + X
double replacement: ions of 2 compounds exchange to form 2 new compounds in aqueous (aq) solutions.
AX + BY --> AY + BX
A, X, B, Y AY, BX -molecular compounds
(reactants)
combustion rxn: substance combines w/ O2 [oxygen gas] releasing a lot of E in form of heat and light
burning of natural gas, propane, gasoline, wood...etcetc
Chapter 7: Chemical formulas and Chemical compounds
7-1 chemical names + formulas
7-2 oxidation numbers
7-3 using chemical formulas
7-4 determining chemical formulas
7-1
In general, the order of nonmetals in binary compound names/formulas is C, P, N, H, S, I, Br, Cl, O, F
oxayanions: polyatomic ions that contain oxygen
salt: an ionic compund made of a cation/anion from an acid
7-2 [another lesson we skipped]
oxidation numbers (oxidation states): distribution of e- among bonded atoms in a molecular compound
general rules
1. atoms in pure element have oxidation # of zero
ex: Na, O2
2. the more electronegative element in binary molecular compoud has #
equal to what it would have as an anion. THe other one cation.
3. Fluorine has oxidation # of -1 b/c is most electronegative
4. Oxygen has -2 except in peroxides (-1) and compounds with halogens (+2)
5. H has +1 in compounds more electronegative than H and -1 in compounds with metals
6. neutral compound: 0 [sum of all oxidation #s]
7. in polyatomic ion, sum of oxidation #s= charge of ion
examples [from book]:
a. UF6
F has -1, so -1 X 6= -6
the compound has a charge of 0, so the oxidation number of U is +6
b.H2SO4
Oxygen/Sulfur more elctronegative than H, so H has +1. (+1)(2)=+2
Oxygen is nor in a peroxide or combined w/ halogen so its 2-. (-2)(4)=-8
+2 + -8 = -6, so sulfur must be +6
7-3 [" "]
formula mass: sum of average atmoic masses of all atoms represented in its formula
ex: KClO3
1 K, 1 Cl, 3 O
39.10 amu [K] + 35.45 [Cl] + 3(16.00amu) [O] = 122.55 amu
percent composition: percentage by mass of each element in a compound
mass of element in sample X 100
mass of sample
> 2 ways to find % composition
mass of element in 1 mole X 100
molar mass of compound
7-4 [" "]
empirical formula: symbols for elements in a compound w/ subscripts showing smallest whole # mole ratio of different atoms in the compound
ionic usually formula unit
to determine empirical formula
1. convert % composition to mass composition
2. mass composition convert to moles
3. smallest whole number mole ratio
ex:
a compound contains 32.38% Na, 22.65% S, and 44.99% O.
1) Mass composition in 100 g sample: 32.38g Na, 22.65g S, 44.99g O
2) 32.38g Na(1mol/22.99g Na)=1.408 mol Na
22.65 g S (1 mol/32.07g S)= 0.7063 mol S
44.99 g O(1 mol/16.00 g O)=2.812 mol O
3) divide each value by smallest one.
1.408/.7063: .0763/.0763 : 2.812/.073
= 1.993 mol Na : 1 mol S : 3.981 mol O
4) round to Na2SO4
Chapter 6: Chemical bonding
6-1 chemical bonding
6-2 covalent bonding and molecular compounds
6-3 ionic bonding and ionic compounds
6-4 metallic bonding
6-5 molecular geometry
6-1
chemical bond: mutual
electrical attr. between nuclei and the valence e- of diff atoms that binds tha atoms together.
ionic bonding: electrical attr. between cations and anions
covalent bonding: sharing of e- pairs between atoms
nonpolar covalent: bonding e- equally shared--> balanced distribution of electrical charge
polar: uneven dist. of charge
polar covalent bond: bonded atoms have unequal attr. for shared e-
H-H
H-Cl
non polar polar cov
6-2
molecule: neutral group of atoms held together by covalent bonds
molecular compounds: chemical compound simplest units are molecules
chemical formula: shows # atoms of each element using atomis symbols, subscripts
diatomic molecule: molecule w/ 2 atoms( group 17, H)
covalent bond
bond length: distance between
2 bonded atoms at minimum potential E. (avg. distance between bonded
atoms)
bond E: E required to break chemical bond and form neutral, isolated atoms
( kJ/mol)
octet rule: chemical compounds
tend to form so each atom by fain/lose/share e- has an octet in its highest
E level
electron dot: only valence e- shown
unshared (lone) pair: e- pair uninvolved w/ bonding that belong to an atom
structural formula: shows kinda, #, arrangement, and bonds in molecule
single bond: 1 pair of e-
resonance: bonding can't be shown properly in 1 lewis structure
6-3
ionic compound: made of cation/anions so when combined, the # of charge are =
formula unit: simplest collection of atoms that can make an ionic compound
lattice E: E released when 1 mol of ionic compound is formed from gaseous ions
*generally ionic compounds have higher
melting/boiling pts than molecular compounds b/c force between
molecules is strong, although in convalent forces within molecules are
strong*
6-4
delocalized e-: do not belong to any 1 atom
-metallic bonding: chemical bonding from attraction of metal atoms and surrounding "sea" of e-
heat of vaporization: measure of strength of the bonds that hold the metal together
6-5
molecular polarity: uneven distr. of molecular charge
vsepr: repulsion between
valence pair e- causes them to be situated as far apart as possible.
vsepr-valence shell electron pair repulsion
linear 180
trigonal planar 120 lone pairs take up space, but its the position of thr ATOMS that
tetrahedral 109.5 determines molecular geometry
bent 105
trigonal planar 107
hybridization: mix 2 or more orbitals of similar E on same atom to make new orbitals of equal E
hybrid orbitals
s,p
sp 2
linear
s,p,p
sp^2 3
trigonal planar
s,p,p,p sp^3 4 tetrahedral
intermolecular forces: forces of attr. between MOLECULES
-dipole: 2 poles (+/-)
-dipole dipole: attr. between polar molecules
-H bonding: H
bonded to highly electronegative atom attrt. to a
lone pair of e- of another electronegative
atom in a
nearby molecule
-london dispersion forces:
intermolecular attr. result from constant
motion of e- and creation of
instantaneous dipoles.
increases with atomic mass
-only forces
on
1.
slightly polar
2.
nonpolar
3.
noble gases
Chapter 5: Periodic Law
5-1 history of periodic table
5-2 electron configuration and periodic table
5-3 electron configuration and periodic properties
5-1
September 1860: Karlsruhe, Germany. International Congress of Chemists
periodic. similarities appear at intervals
elements in periodic table put in order of nuclear charge (# protons in nucleus)
periodic law: physical/chemical props of elements are periodic functions of their atomic #
periodic table: arrangement of
elements in incr. atomic # so elements w/ similar prop. are in same group
lanthanides: elements 58-71
actinides: elements 90-103
5-2
s block: group 1, 2
outer shell: ns^1, ns^2
Group 1: alkali metals
-silver
-soft
-very reactive
-going down the group, elements melt at lower temperatures
-except Li,
Lithium, they have melting pt lower than boiling pt of water
Group 2: alkaline earth metals
-harder, denser, stronger than group 1
-higher melting pts
-less reactive than alkali metals
Transition elements
-typical metal properties
-high luster
-typically less reactive than group 1, 2
-good confuctors of electricity
main group elements: s block and p block
halogens: Group 17, most reactive of nonmetals
5-3
atomic radius: 1/2 distance between nuceli of identical atoms
ion: an atom of group of atoms that have a positive or negative charge
ionizaiton: any process that results in an ion
ionization E: E required to REMOVE one e- from a neutral atom of an element
electron affinity: E change when a neutral atom GAINS an e-
cation: positive charge ion
anion: negative charge ion
valence e-: e- available to be lost/gained/shared in formation of chemicals
electronegativity: ability of atom in a compound to attract e-
periodic trends summary
acoss period left--> right
-atomic radius decreases
why? e- are added to outermost shell, so there's no shielding from more nucleur charge (more protons) so the radius decreases.
-ionization E increases
why? more nuclear charge--> higher attr. to e-, so harder to remove e-
-electronegativity increases
why? increasing nuclear charge (more protons)--> more attraction to e- (negative charge)
down a group
-atomic radius increases
why? the # of valence e- doesn't change, but they are in higher E levels. More shielding from the nuclear charge.
-ionization E decreases
why? b/c in higher E levels (farther from nuclues) so less attraction from nuclear charge, so easier to remove
-electronegativity decreases
Chapter 4: Arrangement of electrons in atoms
4-1 development of new atomic model
4-2 quantum model of atom
4-3 electron configurations
4-1
electromagnetic radiation: a
form of E that shows wavelike behaviour as it moves through
space
electromagnetic spectrum: all forms of electromagnetic radiation
speed of light = 3.0 X 10^8 meters/second
Significance of wave motion: 1. repetitive nature
2. measurable
properties of wavelength/frequency
wavelength: distance between corresponding points on adjacent waves
frequency: # of waves that pass a point in a specific time
wave/sec= 1 Hertz (Hz)
speed of light (3.0 X 10^8) = frequency X wavelength
photoelectric effect: emission of e- from a metal when light shines on metal
Max Plank: proposed that a hot object does not emit electromagetic E continously, but in small amounts called quanta.
E (J)= (6.626 X 10^-34 J s) X (frequency)
^ plank's constant (h)
quantum: minimum amount of E that can be gained/lost by an atom
light-stream of particles. each particle (photon) carries a quantum of E
photon: particle of electromagnetic ration w/ zero rest mass & carrying a quantum of E
E of photon= plank's constant X frequency
for an e- to be ejected, the e- has to be hit by a photon that has the
minimum E to kick it off. mininum E corresponds to minimum frequency.
if the freq. is below minimum, the e- remains bound to the metal
ground state: lowest E state of an atom
excited state: atom has higher potential E than ground
* when an excited atom goes back to ground state, it gives off E in form of electromagnetic radiation *
quantum theory
whenever an excited atom goes back to a lower E state, it emits a photon of radiation.
E of the photon= E (final) - E (initial)= hv
Bohr model
electrons only circle in orbits. the E of an e- is higher when the e- is in an orbit father away from the nucleus
4-2 [although we haven't gone over this in moilanen, i figure it's better to learn anyways]
light can behave as a wave and particle
DeBroglie: - electrons considered waves that were confined to space around nucleus.
-since e- waves exist at specific frequencies,
according to E=hv, the freq.
corresponds to specific energies
(Bohr's orbitals)
diffraction: bending of wave as it passes the edge of an object
e- beams can interfere with each other
interference: overlapping of waves --> reduction of E in some areas/increase in others
Heisenberg uncertainty principle:
it's impossible to determind the location and velocity of an electron or any other
particle.
Quantum theory: mathematically
describes wave properties of electrons and other small
particles.
Shrodinger wave equation... solutions to it are given as wave functions.
wave fuction gives probability of finding an e- at a given place around the nucleus
orbital: 3d region around nucleus that indicates probable location of e-.
quantum numbers: specify properties of atomic orbitals/properties of e- in orbitals
1. principal quantum # (n): indicates main E level occupied by e'
n is always positive
# of orbitals in a shell = n^2
2.angular momentum quantum # (l): indicates shape of orbital
# of orbital shapes=n
values of (l) are 0 and all intergers < n-1
ex: n=2. l= 0, l=1
Letter: s, p, d, f
l: 0,1, 2, 3 in the nth energy level, there are n sublevels
3.magnetic quantum # (m): indicates placement of an orbital around the nucleus
4.spin quantum #: 2 possible values (+1/2, -1/2)
the two spin states of an e- in an orbital
* a single orbital can hold a max of 2 e-, which must have opposite spins*
4-3
electron configuration: arrangment of e- in an atom
* e- in an atom tend to assume arrangement w/ lowest possible E *
ground state e- config: lowest E arrangement of e-
excited state: has higher potential E than ground state
Aufbau principle: e- occupies lowest E orbital that can receive it
Pauli exclusion principle: no 2 e- in same atom can have same 4 quantum #s (opposite
spins)
Hund's rule: orbitals of equal
E occupied by 1 e- before pairing up. All e- in single
occupied orbitals must have same
spin.
highest occupied level: main E level w/ e- and highest principal quantum #
inner shell e-: e- that are not in highest occupied E level
-noble gases: Group 18
-noble gas config: outer main E level occupied fully
| | |
| Chapter 3
3-1
law of conservation of mass:
mass is neither created/destroyed in ordinary chemical/physical rxns.
law of definite proportions: a
chemical compound has same elemets in same proportions regardless of
size of sample.
ex: NaCl [table salt]
always 39.34% Na, 60.66% Cl
^
^ = in mass
law of multiple proportions:
if two or more different compounds are made of the same elements, the ratio of masses of the second element
with
mass of first
element is always ratio of whole numbers.
ex: CO2 <--- 1 g of C, 2.66 g of O
CO <--- 1 g of C, 1.33 g of O
2.66/1.33=2/1 -----> 2:1 ratio
Dalton's atomic theory
1. all matter made of atoms
2. atoms of one element are identicl in size, mass, other properites
3. atoms cannot be subdivided, created, or destroyed
4. atoms of different elements combine in whole # ratios to form chemical compounds
5. in chemical rxns, atoms are combined, separated, or rearranged.
3-2
Structure of Aton
2 regions
-nucleus
-space surrounding nucleus
-nucleus: -located near center of atom
-contains at least 1 proton and usually 1 or more neutrons
-space surrounding nucleus: occupied by electrons
subatomic particles: protons, neutrons, electrons
cathode ray tube
-glass tube filled w/ gas at low pressure
blah blah blah, the results of the crt experiment showed
-cathode rays (e-) had mass
-cathode rays deflected by magnetic field --> e- had negative charge
cathode rays were later named ELECTRONS
*Joseph John Thomson*
1. b/c atoms are electrically neutral [formal charge = 0], they must have positive charge to balance negative charge.
2. b/c e- have so little mass, atoms must have other particles to account for the mass.
Rutherford Experiment
What happened: -fired alpha particles [positively charged] at a gold
foil w/ a screen
around the foil to detect any
particles deflected
- a few deflected back at wide
angles.
-R. reasoned that the ones
deflected back must have hit a small area b/c
not a lot were
affected by it.
-concluded that the nucleus was small, dense, positively charged
b/c positive hit positive --> repulsive force
nuclear forces: forces that hold nuclear particles together
proton-proton
proton-neutron
neutron-neutron
3-3
atomic number: # of protons in the nucleus of each atom of that element
isotopes: atoms of same element w/ diff masses all isotopes of one element have same # of protons. they only differ in
# neutrons
mass #: total # of protons/neutrons in the nucleus of an isotope.
nuclide: general term for an isotope of any element
atomic mass unit (amu): 1/12 mass of carbon-12 atom
average atomic mass: weighted
avg. of atomic masses of naturally occurring isotopes of an element
1 mole= 6.022 X 10^23 particles <-- Avogadro's Number
molar mass: mass of 1 mol of pure substance. usually given as (g/mol)
Chapter 2
2-2
quantity: something that has magnitude, size, or amount
SI: Systeme International
weight: measure of gravitational pull
diff between mass and weight
mass doesn't depend on gravity.
density: how massive objects are compared to their size
-ratio of mass to volume or mass divided by volume
-physical property
-usually decreases w/ increasing temperature
why? most
objects expand as temp goes up, so volume goes up. D=m/V, so
density gets smaller.
D=m/V
SI of density= kg/m^3 derived-> g/cm^3
2-3
accuracy: closeness of measurement to accepted or correct value.
precision: closeness between measurements of a substance obtained in the same way.
percent error:
Value [accepted] - Value [experimental] X 100
Value accepted
sig figs
examples:
number # of sig figs
16341 5
407 3
0.0009 1
850 2
850. 3
direct variation: y/k=x or y=kx
inverse: xy=k
Chatper 1: Matter and Change
1-1: Chemistry is a physical science
1-2: Matter and its properties
1-3: Elements
1-1
chemistry: study of the composition, structure, properties + changes that matter undergoes
chemical: any substance that has definite composition.
ex: water, H2O. has definite composition in terms of the atoms that compose it
basic research: done to increase knowledge
applied research: used to solve a problem in a real-life situation
technological development: production of things that improve quality of life.
1-2
volume: amount of 3-d space an object occupies
mass: a measure of the amount of matter in a substance
matter: anything that has mass, and takes up space (has volume)
the fundamental building blocks of matter are atoms and molecules.
atom: the smallest unit of an element that retains the properties of that element
element: pure substance made up of only one kind of atom
compound: substance made of 2 or more atoms of different elements that are chemically bonded
~Properties are either intensive or extensive
extensive: depends on amount of matter present
ex: volume, mass, amount of E (energy) in a substance
intensive: do NOT depend on amount of matter present
ex: conductivity of heat/electricity, melting/boiling point, density
~physical property:
characteristic that can be observed/measured w/o changing the identity of the substance
ex: melting/boiling pt. <--these points are the temperature that a substance melts or boils.
ice melts--> water (liquid). The substance hasn't
changed; it's still water, only in a
different state of mater.
* physical prop. describe the substance itself, rather than how it can change into other substances *
physical change: change that doesn't change the identity of the substance.
ex: grinding, cutting, melt, boil
change of state: physical change of a substance from one state to another
solid state: -definite volume.shape
-have this characteristic b/c particles are packed in
relatively fixed positions
-particles vibrate around fixed point
liquid state: -definite volume, indefinite shape
-assumes shape of its container
-have this char. b/c although the particles are close,
they are able to flow
around each other
gas state:-no definite volume/shape
-have this char. b/c gases are composed of particles that are very far
apart from
one another compared to the particles of liquids and
solids.
chemical properties:
substance's ability to undergo changes that transform it into a
different substance
chemical change (chemical reaction):
one or more substances are converted into
different substances
*chemical changes do not affect the total amount of matter present
before and after a reaction. The amount of matter, or total mass
remains the same *
law of conservation of energy:
although E can be absorbed/released in
a chemical rxn
[reaction], it is not destroyed/created. [it just
takes
a
different form]
mixture: blend of 2 or more kinds of matter that each have their own identity/properties
homogeneous mix.: unifrom composition [same throughout]
ex: salt water
heterogeneous: not uniform throughout
ex: sand in water [the sand particles stay at bottom]
pure substance: -fixed composition
-every sample has same
exact characteristic properties
-every sample has same
composition
1-3 periodic table
vertical columns: groups or families
rows: periods
metal: element good at conducting heat/electricity
-malleable [easy to shape, can be hammered thin sheets]
-ductile [can be pulled
into wire] [[this is b/c metals have high tensile strength, or
ability to resisty breaking when pulled.
nonmetal: element bad at conducting heat/electricity
metalloid: element that has char. of metals and nonmetals
-all metalloids solid at room temp.
-less malleable than metal, but not as brittle as nonmetals
-semiconductors of electricity
noble gases: generally unreactive
- they rarely form compounds. one is xenon
tetrafluoride
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