Qbank test 1 Flashcards
Rate equation
Intermediates are never in the rate law.
Common ion effect
Will reduce the solubility of a solid.
Hinders product formation.
(Look up rule later in gen chem notes)
Kinetic Energy of a particle/object
KE=1/2m(v^2)
Average KE is only dependent on temp. If molecules are at same temp, they have same KE. (differences in velocity account for mass differences)
Gibbs free energy equation
Tells you whether rxn will be spontaneous
G=H - TS
Laws of Thermodynamics
(1) Energy is conserved
U=Q-W
(2)Spontaneous rxns create entropy
(3)S=0 when T=0K (absolute zero)
Adiabatic system
No heat transfer b/w system and environment.
Removing electrons from d orbital
It is easier to remove electrons from the s orbital before removing from the d orbital.
n+l rule*
Ideal gas law
PV=nRT
Allotrope
Different forms of the SAME element.
If there is any change in the type of atoms “originally” present, it is not an allotrope.
Two major factors that affect chemical rxns
Thermodynamics and kinetics.
Need to think about them BOTH when determining why something is happening.
Heterogeneous vs homogeneous catalysis
Homo=reactants and catalyst in same state
Gives stable structures despite changes in coord. #
Hetero=reactants and catalyst in different states
Zero, First, Second & Third order rate law
Sum of the exponents of the molecules in the rate equation give total order
Oxidation rules
(1) Molecules in free form (H2, O2) have 0 oxidation #
(2) Oxidation of a monoatomic ion is its charge
(3) Sum of oxidation #’s in neutral compound is zero
(4) Oxidation # of grp IA=+1 and IIA=+2
(5) Oxidation # of H=+1 unless in binary metal hydride (-H2) where oxidation #= -1
(6) Oxidation # of O= -2; O= -1 in peroxides and O=+1 w/ Fluorine
(7) Oxidation of fluorine is -1; Cl, Br, I = -1 unless w/ F or O
Catalysis
Alters the rate of a rxn but NOT it’s equilibrium.
Reduces activation E needed.
Aufbau principle
Know how to determine electron configuration.
Fill lowest E orbitals first (build-up)
Formal charge
Formal charge=grp# - (lone pairs) - # of bonds
Review Titration curves
Equivalence pt=when mols of base equal mols of acid
Buffer regions= areas of small pH change
Polyprotic vs monoprotic (# of pKa’s)
Amphoteric species
Compound that can act as an acid or base.
i.e. water
Arrhenius acid/base
Acid=donates H+ to solution
Base=donates OH- to solution
Bronsted Lowry acid/base
Acid=proton donor
Base=proton acceptor
Lewis acid/base
Acid=electron acceptor
Base=electron donor (nucleophiles)
Buffers
To prevent extreme pH changes.
Common ion effect
Know how to interpret phase diagrams
Regions of solid, liquid, gas.
Critical pt=where phases can no longer be distinguished
Hydrogen bonding
-FH, -OH, -NH
Increases melting pt and boiling pt
Lattice energy
Generally decreases when either the cation OR anion increases in size.
Will not matter if both cation and anion increase in size at the same time.
Types of reactions
Single displacement Double displacement Neutralization (acid/base) Oxidation/reduction Precipitation Combustion (oxygen) Combination Disproportionation=opposite of combination
Graham’s law of diffusion
(v1^2)MM1=(v2^2)MM2
Strength of an ionic salt
Made of the most electropositive and electronegative elements (metal & nonmetal)
Steps of a Free Radical Reaction
Write it out
3 steps
Initiation (radical formation)
Propagation (rxn can still go on)
Termination (stops rxn from going on)
Oxidation vs reduction
Oxidation means becoming positive (losing electrons)
Reduction means becoming negative (gaining electrons)
What environment do gases prefer?
Increased volume
Low pressure
Higher temp
van der Waals equation
(P+(n^2 x a)/(V^2)) x (V-nb) = nRT
This equation is used when the gas being described is not ideal (high pressure and low temp)
Solubility rules
(1) All alkali (IA) salts soluble
(2) All NH4+ salts soluble
(3) All Cl-, Br-, I-soluble EXCEPT Ag+, Pb+, Hg2 2+
(4) All SO4 2- soluble EXCEPT Ca2+, Sr2+, Ba2+, Pb2+
(5) All oxides insoluble EXCEPT CaO, SrO, BaO, alkali
(6) All OH- insoluble EXCEPT Ca2+, Sr2+, Ba2+, alkali
(7) All CO3 2-, PO4 3-, S2-, SO3 2- insoluble EXCEPT alkali, NH4+
(8) All Na+, NO32- salts soluble
H+ conc. and pH equation
pH= -log [H+]
Osmotic pressure equation
osmotic pressure (pi symbol thing) = MRT
R=0.0821
Electrolysis equation
mass of material = it/nF x formula weight of material
n=moles of electrons transferred
Avogadro’s volume
at STP = 22.4 L/mol
Know how to balance half reactions
Will not always get the reaction in the passage.
This affects the moles of electrons you are dealing with
Charge density
First determined by the charge an ion does or does not have.
If two ions have same charge then whichever is smaller (hold electrons more tightly) will have greater charge density.
Heating curves
Review them.
Slope=change in T/q
Ksp
Increases with increased temperature (generally)
STP
1 atm
0 C or 273 K
22.4 L/mol
Vibrational frequency of bonds
Depends on the masses of atoms involved (m) and the bond strength (k)
f=(1/2pi) x sqrt(k/m)
