review sheet including equations and constants
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REVIEW SHEET including EQUATIONS and CONSTANTS
ATOMIC STRUCTURE
MASS SPECTROMETRY
---------------------------------------------------------------- PERIODIC TRENDS IN PROPERTIES:
Periodic TrendsFor periodic trends consider: All periodic trends rely on Coulomb's law.
1. If the things being compared have the same number ofoccupied energy levels, depend on the # of protons.More protons=more pull. Go to the trend below.
2. If the things being compared have a different numberof occupied energy levels, the thing with more occupiedenergy levels has valence electrons farther from thenucleus so there is less pull on those electrons. Go tothe trend below.A. Ionization energy--Closer electrons, morepull=higher IE. More protons, more pull, morepull=higher IE.B. Radius (either atomic or ionic or both)--Less layersof electrons=smaller size. Same # of layers, moreprotons=smaller electron cloud/size.C. Electronegativity--the amount of pull or "lust" forelectrons in a bond. Less layers of electrons=closer tothe nucleus=greater electronegativity. Moreprotons=greater electronegativity.D. Electron affinity--energy released when an electronis added (opposite of ionization energy). More layersof electrons=farther away=less energy released. Moreprotons=more energy released.
Fr = largest & lowest IE (least Zeff, most shielding)
d orbitals Groups 3-12:
transition metals
smallest & highest ionization energy = He most electronegative & reactive = F
p orbitals
Group 17: halogens
Group 18: noble gases
Group 1: alkali Group 2: alkaline earth
s orbitals
↑at
trac
tion
(↓ s
hie
ldin
g)
↑attraction (↑ Zeff)
weighted average atomic mass = (mass1 · %) + (mass2 · %) + (mass3 · %) + …
BONDING & IMFs
Coulombic Attraction: F ∝ 𝑞1𝑞2
𝑟2
q = charge (more charge is more attraction) r = radius (more
distance is less attraction)
-------------------------------------------------------------------- LEWIS STRUCTURES
Count-------Connect-------Octet-------Octet-------Mult. Bonds (val e–’s) (bonds) (outer) central) (double or triple)
Formal Charge = val e – #lone e – #bondsWant a formal charge of 0 for all elements, but if any element is negative, it must be the most electronegative.
-------------------------------------------------------------------- IMFs• H-bonds a SUPER polar DP-DP. A H attached to F, O, or N is attracted
to a F, O, or N on another molecule.
• dipole-dipole int’s (polar ) (stronger with greater ∆electronegativity)
• dispersion forces, LDFs (nonpolar )(temporary dipoles)
(stronger with more e–’s , more polarizable) -------------------------------------------------------------------- ATTRACTIONS IN SOLIDS, LIQUIDS, & GASES Attractions in Solids, Liquids, & Solutions
Molecular
Covalent-Network
Ionic
Metallic
Soft
Low mp & bpPoor conductor
Very hard
Very high mpPoor conductor
Hard and brittle
High mpConducts as (aq) or (l)
Soft to very hard
Low to very high mp
Malleable, Ductile, Conductor
Ar I2 CO2 H2O C2H5OH C11H22O11
C(diamond)
SiO2
WC2
NaClCuSO4
All metals& alloys: Cu, Fe, K, Al,…
Covalent Bonds (network)C(diamond) , SiO2 (quartz) ,WC2 (tungsten carbide) , etc…
Ionic Bondscrystal lattice of charged ions
Intermolecular Attractions (IMAFs)London dispersion forces
Dipole-dipole interactions
Hydrogen bonds
Type Forces Between Particles Properties
d- d+
- +q1q2
d
(nonpolar)(polar)
(H with N, O, F)
Metallic Bonds+ metal ions indelocalized “sea” of e–’s
• harder and higher mp of solid (higher Hfusion)• higher bp of liquid (higher Hvaporization)• higher viscosity (resistance to flow)• lower vapor pressure (less vapor above a liquid)
Stronger Attractions cause…
Unit 1 Unit 2, 3a
MASS , COMPOSITION , STOICH , & SOLUTIONS
mass % = g part
g total sample × 100%
% yield = experimental
theoretical× 100%
% error = |experimental−theoretical|
theoretical× 100%
moles (n) = mass (g)
molar mass (MM)
Find EMPIRICAL & MOLECULAR FORMULA:
1) % to mass (g) (if %’s given, write as grams) 2) mass to mol (convert with molar mass) 3) ÷ by small (to get lowest ratio) 4) times ‘til whole (if necessary, x by 2 or 3)
molecular mass
empirical mass= multiple of empirical →
-------------------------------------------------------------------- STOICHIOMETRY ___ g A x 1 mol A x mol B x B = g A mol A mol B (molar mass) (mole ratio) -------------------------------------------------------------------- ELECTROLYTES: ionize or dissociate into charges (strong, weak, non) in solution conducting electricity
Always soluble ions: SNAP (Na+, NO3–, NH4
+, K+)
Concentration [ ] in Molarity, M = moles solute
L solution
M1V1 = M2V2 (dilution) 1000 mL = 1 L -------------------------------------------------------------------- SOLUTION FORMATION
Molecular Formula
6.022 x 1023 1 mole
Unit: g B , or L B , or particles B , etc.
Whatever unit of B asked for.
(if given grams A)
ACIDS & BASES
Acid: donates proton (H+)
HA + B → BH+ + A– (acid) (conjugate base)
Strong Acids (completely ionize) HNO3 , H2SO4 , HCl HBr HI , HClO4 ------------------------------------------------------------------- Base: accepts proton (H+)
HA + B → BH+ + A– (base)(conjugate acid)
Strong Bases (completely ionize) hydroxides (OH–) of Group 1 and CBS
LiOH NaOH KOH , Ca(OH)2 Ba(OH)2 Sr(OH)2
-------------------------------------------------------------------
REACTIONS Net Ionic Equations (NIE’s) Complete------Dissociate------Cross------Net------Bal (molecular) (strongs & SNAP) (spectators)
REDOX (OX#’s change) (elements have OX# 0)
half RED: O20(g) + 4 e– → 2 O2–(aq)
rxns OX: Mg0(s) → Mg2+(aq) + 2 e–
1) Synthesis 2 Mg0 + O20 → 2 MgO
2) Decomposition 2 H2O → 2 H20 + O2
0
3) Single Replacement(metal + acid)
Zn0 + 2 H+ → Zn2+ + H20(g)
Single Replacement(metal + metal ion)
2 Na0 + Fe2+ → 2 Na+ + Fe0
4) Combustion CH4 + O20 → CO2 + 2 H2O
NOT REDOX (same ions w/ same charges, just switch partners) 5) Double Rep.
(Precipitation)Ag+ + Cl– → AgCl(s)
Double Rep.(Acid-Base)
HC2H3O2 + OH– → C2H3O2– + H2O
Double Rep. (acid + carbonate)
MgCO3 + 2 H+ → Mg2+ + H2O + CO2(g)
BEER-LAMBERT LAW (LAB)
concentration determined by light absorbed thru solution
A = bc A = absorbance = molar absorptivity (M–1cm–1) b = path length (cm) c = concentration (M)
Greater A (absorbance) , Higher c (concentration)
Endo
solute-solute att’s break
Endo
solvent-solvent att’s break
Exo solute-solvent
att’s form
more soluble with more similarsolute-solvent att’s
(similar IMAFs or ion-dipole)
Unit 1, 3b, 3c, 4c
Unit 3d
Unit 4a
Unit 4c
if REDOX: O HE BAL U
(no spectator ions shown)
KINETICS
Rate of rxn depends on: 1) collision frequency2) collision energy (Eact)3) proper orientation of particles
↑ exposed surface area = more frequent collisions ↑ concentration = more frequent collisions ↑ Temp = more frequent collisions & more KECatalysts speed up rxns by lowering activation energy. The highest activation energy in a stepwise graph is the rate determining step. ---------------------------------------------------------------- Rate = k[A]m[B]n (general rate law) shows reactants in RDS (slow step) of mechanism ---------------------------------------------------------------------- [A]t = concentration of A after some amount of time[A]0 = initial concentration of A
0th order: rate law: ------------------------------------- ------------ -----Rate = k
integrated rate law: [A] t – [A]0 = –kt
----------------------------------------------------------- 1st order: rate law: Rate = k[A]1
integrated rate law: ln[A]t – ln[A]0 = –kt
1st order has constant half-life (t1/2)
t1/2 = 0.693
k
----------------------------------------------------------------------------
2nd order: rate law: Rate = k[A]2
integrated rate law: 1
[A]t−
1
[A]0 = kt
[A]
slope = –kt
time
time
ln[A
]
slope = –k
0th b/c A is not areactant in the
RDS (slow step)of mechanism
time
slope = k
1 [𝐴]
PE
catalyzed lower Eact
(intermediate:
Rate is M/t so: Rate = k M = ?
tunits of k: M·t–1 t is s OR min OR etc.
Rate is M/t so: Rate = k[A]1 M = ? · M
tunits of k: t–1 t is s OR min OR etc.
Rate is M/t so: Rate = k[A]2 M = ? · M2
tunits of k: M–1·t–1 t is s OR min OR etc.
produced then consumed)
activation energy GASES
PV = nRT (Ideal Gas Law)
P = pressure 1 atm = 760 mmHg = 760 torr V = volume (L) 1 L = 1000 mL n = moles
R = gas constant 0.08206 L∙atm
mol∙K𝑶𝑹 62.36
L∙torr
mol∙K
T = temperature (K) C + 273 = K ----------------------------------------------------------------
MM = mRT
PV (molar mass of a gas)
----------------------------------------------------------------
PA = Ptotal × XA mole fraction, XA = moles A
total molesPtotal = PA + PB + PC + …
----------------------------------------------------------------
STP = 273.15 K and 1.0 atm
22.4 L·mol–1 @ STP (volume of 1 mol of gas) ----------------------------------------------------------------
Density(D) = m
VMM =
DRT
P
KEmolecule = 1
2𝑚𝑣2
m = mass (or molecular mass) v = velocity
lower mass (↓m) , faster speed (↑v) higher Temp (↑KE) , faster speed (↑v)
---------------------------------------------------------------- IDEAL vs NON-IDEAL
Most ideal with weakest IMAFs and at:
• high Temp b/c IMAFs are negligible (high KE)
• low Pressure b/c particle volume is negligiblecompared to great total volume
lower Temp
higher Temp
Unit 3b Unit 5
THERMODYNAMICS
–H = exothermic(heat lost to surroundings so Temp)
+H = endothermic(heat absorbed from surroundings so Temp)------------------------------------------------------------If rxn is reverse, … then H is opposite (–H).
If rxn is multiplied by 2, ½, 3, etc…. …then H is multiplied by that number, too.
If rxn 1 is added to rxn 2, ... …then H1 is also added to H2 ------------------------------------------------------------
∆H= (bonds broken) – (bonds formed) ------------------------------------------------------------ CALORIMETRY (LAB)
q = mcT q = heat energy (J) m = mass (g) (if a solid is added to a solution, the mass is the total of the two) Put in the mass of the thing that changed temperature.
c = specific heat capacity (J
g∙℃) or (
J
g∙K)
T = change in temperature (℃) or (K)
Hsystem = –qsurroundings
convert J to kJ and ÷ by moles to get “molar heat of rxn” (Hrxn in kJ/mol)
c = specific heat capacity (J
g∙℃) or (
J
g∙K)
means the amount of heat energy lost OR gained to change 1 g of matter by 1oC.
----------------------------------------------------------------- HEATING CURVES
In Sections Q and S, added heat does not increase KE (Temp), but increases PE by overcoming attractions and separating particles to change phase.
solid
liquid
gas
Q: melting q = n · Hfusion
S: boiling q = n · Hvaporization
R: (q = m·c·T)
Unit 6 EQUILIBRIUM
aA + bB ⇌ cC + dD [ no (s) or (l) in K expressions ]
Kc = [C]c[D]d
[A]a[B]b (conc’s in M) (aq) OR (g)
Kp = (PC)c(PD)d
(PA)a(PB)b (P in atm) (g) ONLY
K > 1; more products than reactants @ equilibrium K < 1; more reactants than products @ equilibrium
------------------------------------------------------------------- If rxn is reverse, … then K is inverse (1/K OR K–1)
If rxn is multiplied by 2, ½, 3, etc…. …then K is raised to that power: K2 , K½ , K3, etc.
If rxn 1 is added to rxn 2, ... …then K1 is multiplied to K2 ------------------------------------------------------------------- Q (reaction quotient) K = Q ; at equilibrium K<Q ; too much product, shift left form reactant K>Q ; too much reactant, shift right form product-------------------------------------------------------------- AmBn(s) ⇆ mA+(aq) + nB–(aq)
Ksp = [A+]m[B–]n (solubility product constant)
K= Q; saturated K<Q ; saturated, shift left to precipitate solid K>Q ; unsaturated, shift right dissolve into ions
Common Ion Effect: shift left (less soluble) -------------------------------------------------------------------------------
Use RICE tables to track what changes during rxn: R eaction (shows mole ratios as coefficients) I nitial (write units! mol OR M OR atm) C hange E quilibrium (write units! mol OR M OR atm)
- Add R or P:
- Remove R or P:
- Volume: ↓V shifts to
↑V shifts to
- Temp.
↑T shifts
↓T shifts
- Catalyst or non-reactive gas (He, Ne, Ar):
shifts away from the additionshifts toward the removal
fewer mol of gas (↓ngas)
Le Châtelier’s Principle
more mol of gas (↑ngas)
no shift
(changes K)(Heat + R ↔P)(R ↔P + Heat)
(Ptotal)
in endo dir. to use up heat
in exo dir. to make more heat
System at equilibrium disturbed by change (affecting
collisions) will shift ( or →) to counteract the change.
Unit 7
Temp behaves like any reactant or product.
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