General Chemistry Flashcards
what is the definition of % mass solution??
Mass solute/ ( mass solute + mass solvent = mass solution )
3 fold dilution
- dilute to 3x less than initial
- 2 part water and 1 part solution
Oxidation
it loses electrons
mneumonic “ OIL RIG”
OIL - oxides it loses e-
RIG = Reduction it gains e-
reduction
gains electrons
Reducing agent
helps reduce other agents ( REDUCTANT) and it get oxidized
oxidizing agent
acts like an oxidant ( oxidizes other reagents) and gets itself redued.
Solubility Rules: Salts containing Alkali metals cation with ( Li+, Na+, K+, Cl-)
water soluble
Solubility Rules: Salts containing Nitrate( NO3-)
water soluble
Salts containing halide anion( Cl-, Br-, I-)
water soluble except Ag+, Pb2+
Solubility Rules: Salts containing (SO4) 2-
sulfate
water soluble except Ba2+, Pb 2+, Hg 2+, Ca2+
Solubility Rules: Salts containing ( OH-) hydroxide
are slightly water soluble.
- KOH and NaOH are substantially soluble, while Ca(OH)2, Sr(OH)2, and Ba(OH)2 are fairly soluble
Solubility Rules: Salts containing Carbonate( CO3) 2-, chromate ( CrO4-), phosphate anion ( PO4) 3-, sulfide ( S2-)
Slightly soluble
MNEUMONIC FOR LIMITING REAGENT
mole ratio A/B > balanced mole ratio A/B
then what is the limiting reagent?
mole ratio A/B
mole ration A/B > balanced mole ration A/B
THEN B is the limiting reagent
mole ratio A/B
oxidation state of oxygen
-2 except with peroxide
oxidation state of hydrogen
+1
oxidation state of halide
-1
1/5=
0.2
1/6=
0.166
1/7=
0.143
1/8=
0.125
1/9=
0.111
1/10=
0.1
1/11=
0.091
1/12=
0.083
for molecular molecules, the number of hydrogens must be
it must be an even number
Does molality change with temperature?
NO , molality doesn’t change with temperature
Does molarity change with temperature
Yes, molarity changes with temperature
Does density change with temperature
Yes, density changes with temperature
Does specific gravity change with temperature
Yes, specific gravity changes with temperature
Lower pKa ->
stronger acid and weaker base
Higher pKa
weaker acid and stronger base
if pH >pka, the molecule is?
deprotonated
if pH
protonated
Solid >—solid/liq—-> Liquid—> lig/gas—> gas
is what kind of process
endothermic ( it absorbs energy to break the bonds and release the molecules)
mneumonic - it takes energy to break bonds
Solid
exothermic ( release energy as bonds are made)
Mneumonic - when bonds are made, everyone is happy and energy is released.
Name the types of systems in thermodynamics
- isolated
- closed
- open
Define Isolated system
no exchange of hear, work, or matter with surroundings
Define closed system
exchange of heat and work, but no matter with the surrounding
Define open system
exchange of heat, mass, and work with the surroundings
Define a state function
a system that is path -independent and depneds only on the initial and final states
examples: delta H ( enthalpy) Delta S ( entropy) Delta G ( Gibbs free energy) delta U ( internal energy change)
Conservation of Energy
- the total amount of energy in an isolated system remains constant.
total energy is neither gained nor lost, it is merely transferred between the system and its surrounding
.
define Endothermic reactions
Energy is ABSORBED by the reaction in the form of heat.
delta H is positive
MNEUMONIC : H STANDS FOR HEAT
Define exothermic reactions -
energy is RELEASED by the reaction in the form of heat
Delta H is negative
MNEUMONIC : H STANDS FOR HEAT
delta H is the change in heat content of a reaction
+ means heat is ABSORBED
- means heat is RELEASED
Bond dissociation energy define
it is the energy nrequired to break bonds
Energy in the reactants - products
the sign is POSITIVE because energy is required to break bonds
define Entropy
a measure of disorder
measured in J/K
Entropy of gas>liqiud>solid
define free energy
Free energy is the energy available that can be converted to do work.
Delta G = Delta H - T delta S
T is in kelvin
Sponantenity of a reaction relies on what?
Gibbs free energy
Spontaneous reaction has what sign of delta G
NEGATIVE aka exogonic
NONSPONTANEOUS reaction has what sign of delta G
POSITIVE aka endogonic
NONSPONTANEOUS reaction has what sign of delta G
POSITIVE aka endogonic
First law of thermodynamics
Del U= Q+W
is based on the principle of conservation of energy, and it basiclaly says that the change in total internal energy of a system is equal to the contributions from work and heat.
what is the Q in the first law of thermo?
HEAT
Q is positive –> the heat is being absorbed
Q is negative –> the heat is being released
What is the W in the first law of thermo?
WORK
Work is positive - when work is being done ON the system
Work is negative - when work is being done BY the system.
Second law of thermodynamics Entropy
- 2nd law states that the things like to be in a state of hihger entropy and disorder
- an islolated system will increase in entropy over time
- an open system can decrease in entropy, but only at the expense of a greater increase in entropy of its surroundings
The universe as a whiole is increasing in entropy.
delt S >= q/t
reversible systems Delt S=q/t
irreversible systems det D>q/T
define heat of fusion
del H fusion = energy input needed to melt something from solid to liquid and vice versa
latent heats are measured as Joules/mass
therefore Q=mL where m = mole and L= latent heat of vaoprization or fusion
define heat of vaporiation - delt H vap =
= del H vap= energy input needed to vaporize something from liquid to gas and vice versa.
latent heats are measured as Joules/mass
therefore Q=mL where m = mole and L= latent heat of vaoprization or fusion
Area of a PV diagram gives you what?
WORK!
PV diagrams depict thermodynamic processes by plotting pressure againsst volume
Name the types of processes in thermodynamics
- adibatic process
- isothermal processs
- isobaric process
- isovolumetric ( isochoric ) process
Define Adiabatic process
- NO heat exchange
Q=0
Det U = W
Isothermal Process
no change in temperature aka delta U = 0
the change in work = change in heat
isobaric process
constant pressure
W=Pdet V
P=0
Isovolumetric process ( isochoric(
no change in volume.
work = P det V=0 because there is no change in volume.
det U = Q
Mole M = It/nF
Helps determine moles of element being depositied on a plate
“ moles of M” it is eNouF
Electrons flow which way? Anode to cathode or cathode or anode?
Anode to Cathode ( negative charge flows away from Negative anode)
A—-> C
Current ( +) Charge flows cathode to anode or anode to cathode
Cathode to anode ( posituve charge flows away from positive cathode)`
C—-> A
Arrhenius Equation
k=Aexp(-EA/RT)
k=rate constant
A= frequency factor
EA=activation energy
R= Ideal Gas Constant
T= temerature
A decrease in EA or Increase in T will increase K
Arrhenius Equation
k=Aexp(-EA/RT)
k=rate constant
A= frequency factor
EA=activation energy
R= Ideal Gas Constant
T= temerature
A decrease in EA or Increase in T will increase K
NOT DEPENDENT ON ENTHALPY
Lower the pka=more acidic
Resonance can help stablize
- relative aciditity of a acid can be judged on the stabilization of its conjugate base of that acid
the stronger the acid, the more stablized the base,
Gibbs free energy formula
delt G=del H-T Del S
Del H=enthalpy
Del S= Entropy
- del H - del S ( same sign temp dep) LOW T
+ del H + del S ( same sign temp dep) HIGH T
-del H + del S EXOTERHMIC
+delH - del S Endothermic
Solubility of molecules in a solute depends on temperature and its nature of solute and solvent
example: N2O gas at 248 compared to 298
Gas in lower temperature will dissolve better in fluid - additionally since H2O is polar- it will dissolve polarity better than nonpolar.
Atomic Number
Atomic Number identifies the atom –> will tell you the number of proton
Mass Number
mass number will indicate the entire mass of the atom
Neutron + proton
During a phase change, what is constant?
During a phase change, temperature is constant!!
Convection is defined as ?
Convection is defined as the movement of heat through liquid and gas
Hund Rule
Parallel spin 1st occupy degenerate orbital that are parallel spins
Aufbau principle
fill up the lowest orbiral first
Pauli exclusion principle
opposite spin and no atom can have the same quantum numbers
Changes in del S, del H, and Del G are state functions
therefore it only depends on its initial and final states
independent of path
pKa +pKb=14 only applies to compounds
pka of acid and pka of conjugate base OR
pkb of base with pka of its conjugated acid
Bronsted lowry acid =
Donate H+
Bronsted Lowrey Base
Accept H
Lewis Acid
accept electrons
Mneuominc : Lewis - think lewis strucures and electrons
ACid = Acceptance
electron acceptance
Lewis base
donate electrons
Mneuominc : Lewis - think lewis strucures and electrons
Lewis base
donate electrons
Mneuominc : Lewis - think lewis strucures and electrons
“Strong” and “Weak” is respect to acid and bases - in terms of the degree to which it dissociates
Strong acid = 100% complete dissociation
therefore how much of Acid present compared to its conjugate base
rate law /constant = wht
rate=k[A][B]
is there is an increase in temperature, k increases and therefore the rate constant also increases
thermodynamic properties are not involved with kinetics
- it deals with equilibrium ( thermodynamics)
- kinetics = deals with how to get the reaction to where it needs to be.
Exothermic reactions deals with thermodymanics or kinetics?
thermodynamics?
if there is BOILING POINT question, look for HB
increase HB causes increase in BP
TLC plates ( aka thin layer chromatrography) - are silica plates that are very polar aka the stationary phase is polar
mobile phase = nonpolar substance
molecule with affinity for polar phases will have a lower Rf
nonpolar molecules will have a greater Rf
Rf is calculated distance substance traveled / mobile phase line traveld.
Which atom has the smallest radius?
K
K+
Ar
Cl-
K+, Cl- and Ar are all isoelectic - which means they al have the same number of electrons YET the K+ have more protons which increases the Zeff therefore making the radius the smallest
Most ideal gases experience very WEAK intermolecular forces WHY ? it wants to reduce the pressure component
HCl + NaOH = polar
HF + NaOH = polar
HF + CH4 = polar
HCl + CH4 = both are nonpolar and they have very low intermolecular forces
at the equilvance point
mole H + = mole OH -
Need to keep in mind of the molarity
NaVa= NbVb
at the equilvance point
mole H + = mole OH -
Need to keep in mind of the molarity
NaVa= NbVb
Potassium
K–> K+ e- exothermic reaction
Normally all the small alkali metals are spontaneously reactive
Gram eq weight defintion
molar mass/ number of protons
EMF = E red, red - E red, ox
Reduced = more positve Emf = therefore has the ability to do work since it agained Electrons and it gained ENERGY
Gas –> solid is called what?
deposition
SOlid –> gas
sublimiation
Liquid -> gas
vaporization
Gas –> liq
condensation
Solid –> liq
meltilng
liq- solid
freezing
Hydrogen bonding only occues when?
only occures when molecules have F,O,N and directly bonded to hydrogen.
inert gas has what type of molecular interaction?
london dispersion
Absolute O is when?
0 Kelvin
Isothermal occurs more slowly
adiabatic = occur quickly * therefore the graphs look more sleep ) ( no heat exchange(
when trying to determine if something is compressed or expanded, look at the volume ( final - initial )
Lewis Acid -
Accepts electrons
Molecules with incomplete octet ( AlCl3, BF3)
- simple cation except ( alkali + heavy alkaline earth metal )
- smaller cation with high charge = more electropillic
Lewic base
Donates electrons
Bronsted Lowey Acid
DOnate proton
Bronstred Lowry Base
Accept proton
Arrehnis acid
Makes H+
Arrenhenis base
makes OH
Strong Acid Name them
Hydroiodic Acid HI HydroBromic Acid HBr Hydriochloric Acid HCl Nitric Acid HNO3 Percholoric Acid HClO4 Choloric Acid HClO3 Sulfuric Acid H2SO4
Strong Base
Sodium Hydroxide NaOH Potassium Hydroxide KOH Amide Ion NH2 - Hydride H- Calcium Hydroxide Ca(OH)2 Sodium Hydroxide NaOH Calcium oxide CaO
Acid disscociation decreases with acid concentration
think about the le chatlier principle if too much protons around, less likely to move
Hydride
basic / netral = Hydride + Metal ( NaH(=)
Acid/Neutral = Hydride = nonmetal
Acidity of a nomental hydride transds to increase going down a periodic table ( probably becayse it doesnt want to hang on to its protons any more )
H20 < H2S< H2Se< H2Te
Hydride
basic / netral = Hydride + Metal ( NaH(=)
Acid/Neutral = Hydride = nonmetal
Acidity of a nomental hydride transds to increase going down a periodic table ( probably becayse it doesnt want to hang on to its protons any more )
H20 < H2S< H2Se< H2Te
Strong acid titarte with weal base
Ph < 7
Strong base with weak acid
pH > 7
Weak acid and weak base
if pKa of acid is lower than pKb of base then ph of eq pt will be ph<7
if pkb of base is lower than the pka then the pH of the eq point will be greater than 7
In galvanic cells EMF = +
In electrolytic Cells EMF = -
Reduction always occurs in the cathode
oxidation always occurs in the anode k
In terms of electrochemistry, oxized element will have more negative potential than the one being reduced in an galvanic cell
In a galvanic cell- the reduaction potential of the cathode cannot be less the anode because
emf = Ered, cat- E red, anode and the EMF must be postive
Metal gives up electrons
Nonmetals take electrons
Acid ending in - ic makes anions ending in - ate
sulfuric acid –>sulfate
ate has more oxygens than ite
acid ending in - ous makes anions ending it - ite
US we AIGHT
nitrous acid –> nitrite
Affinity Chromatorgraphy -
coat beads with receptor and the ligand will bind. Once the protien is retained, elute by washing with free receptor adn it will release it off the bead
Size exclusion chromatography
Bead with small poes - smaller the size, the more slowed down because small object get stick in a small pore.
Ion exchange chromatography
column coated with charged substance so it will bind to compoung with opposite charge
Extraction
Used to separate organic and aquaous phases
Filtration
seperate solid from liquid
name the types of distillation
- simple
- vacuum
- fractional
Simple distillation
when the boiling point is more than 25 degrees apart from each other
fractional distillation
when the two boiling points are 25 degrees within each other
vacuum filtration
when the boiling points are greater than 150 C and need to decrease boiling point and its vapor pressure
vacuum filtration
when the boiling points are greater than 150 C and need to decrease boiling point and its vapor pressure
Boiling point of a liquid= temperature at which the vapor pressure of the liquid = the surface pressure
normal boiling pressure point is measured at 1 atm pressure.
Vapor pressure increases with temperature.
if the surface pressure decreases then the boiling point decreases
therefore in a vacumm, the surface pressure is low therefore the boiling point is low.
if there is aleak in the system, the surface pressure will increase and therefore increase the boiling point
When atoms have the same number of electrons, the number of protons ( greatest will have the smallest size)
this is because it has the greatest number of protons which will cause more pulling and the Zeff will be higher in this case
More arrangement = entropy is decreased
entropy typically means disorder
gamma rays = represent ionizating energy
that is why is it horrible for yu.
formal charge =
of valence electrons - sticks-dots
at side chain pka, 50% protonated and 50 % deprotonated
this is where the half eq point happens where conj Base = acid and the concentrations are the same
pH+pOH= 14
Ka*Kb=Kw=10^-14
pKa + pKb = 14
pkb ( add base to water )
B- + h20 –> HB + OH -
kb= [HB][OH-]/[B-]
pka ( add acid to water )
HA + h20 —> A- + h3o+
pka = [A-][h3O+]/HA
pH+pOH= 14
Ka*Kb=Kw=10^-14
pKa + pKb = 14
pkb ( add base to water )
B- + h20 –> HB + OH -
kb= [HB][OH-]/[B-]
pka ( add acid to water )
HA + h20 —> A- + h3o+
pka = [A-][h3O+]/HA
During titrations, it is important to note if it is monoprotic or diprotic. it is also good to note if it starting as an acid or a base. A good way to determine this is see what the acidity or basicity is if there is no titrant added. this will tell you where you should start.
acid titraated with strong base = start acidic
base titrated with strong acid = start basic
note you can only titrate with strong acid and strong bases because it will fully dissociate
During titrations, it is important to note if it is monoprotic or diprotic. it is also good to note if it starting as an acid or a base. A good way to determine this is see what the acidity or basicity is if there is no titrant added. this will tell you where you should start.
acid titraated with strong base = start acidic
base titrated with strong acid = start basic
note you can only titrate with strong acid and strong bases because it will fully dissociate
galvanic cells and concentration cells do not use a battery. it is spontaneous. in terms of the line notation it goes anode || cathode
in concentration cells, the anode is less concentratied and the cathode is more concentrated.
geometry / shape refers to the position of the atoms not the electrons
molecular geometry - where atoms are located
electron geometry - where elctrons are located.
air bubbles are often inserted into a boiling system to prevent superheating.
acts similar to boiling chips.
define first ionization energy
first ionization energy si the energy required to remove an electron from the outer shell of an atom.
for a given period, it is the loweest when the removal of the electron results in a complete shell or subshell, and the highest when the removal of the electron disrupts a full complete shell or subshell.
noble gases will have the highest ionziation energy and the alkali metals ( potasium for example) - will have the loweest highest ionization energy.
define first ionization energy
first ionization energy si the energy required to remove an electron from the outer shell of an atom.
for a given period, it is the loweest when the removal of the electron results in a complete shell or subshell, and the highest when the removal of the electron disrupts a full complete shell or subshell.
noble gases will have the highest ionziation energy and the alkali metals ( potasium for example) - will have the loweest highest ionization energy.
to determine the number of protons and neutrons an atom has - look at the mass number and its atomic number…. the atomic number will indicate the protins and you can substrae that from the mass number to get the number of neutrons
in order to determine the number of elecctrons, protons = electrons if the charge is neutral.
to determine the number of protons and neutrons an atom has - look at the mass number and its atomic number…. the atomic number will indicate the protins and you can substrae that from the mass number to get the number of neutrons
in order to determine the number of elecctrons, protons = electrons if the charge is neutral.
hydrogen = metal or nonmetal
nonmetal
molecules that contain strongly electron withdrawing or electron donating substituents - are highly polae and posses high dipole moments
example glycine AA molecule. COOH and the NH3 groups make strong dipole
rate constants must have units in inverse time ( s^-1)
0 order : not dependent on concentration
1st order : rate order unit is ( s^-1 )
2nd order : M^-1 * s^-1
define coordination number
coordination number typically occurs in coordinated covalent bond such that it describes the numeber of moelcules are around the ion.
Bond enthalthy
the amount of heat required to break a bond
therefore the smaller the bond, the stronger the bond and more energy required to break it.
