ap chem exam

closed system is one where…

only energy (heat) can move in and out

delta E =

q + w

work (done by gas?)=

- P (delta V)

fusion is

s to l

Abs temp =

average KE

bc Temp = AKE, it means gas molecules will collide more frequently with the wall, not more _

energetically

law of conserv energy :

Q of system + Q of surroundings = 0

Q of system =

- Q of surroundings

because gas particles are so far apart, gases have … density and are … compressible

low and highly

surface tension

tendency of liquids to minimize their surface area due to IMFS

viscousity

resistance to flow

adhesion

attraction of molecules of different substances due to IMFs, paper and tape

meniscus

when liquid molecules are more attracted to the molecules of the container

surface tension

the energy required to increase the surface area of a liquid by a unit of area.

When forming more complex molecules, the entropy (ΔS) of the system generally increases

This is because more complex molecules have more ways to vibrate, rotate, and move, leading to a greater number of possible microstates and thus a higher overall entropy. 

increasing entropy is increasing

dispersal

WATCH OUT FOR __ UNITS

entropy

when delta g is neg, , if = 0, than…

it’s spontaneous reaction, equilibrium

delta g =

delta g knot + RT ln Q

when delta g = 0, the system is _

at equilibrium and K = Q

if K greater than 1…

that means products are favored because the [products] is greater than [reactants]

if k is less than 1,

reactants are favored

at equilibrium, the more neg delta g is, the __ the magnitude of K

greater

at equilibrium, the more pos delta g, the __ the magnitude of k

smaller

you _ multiply Ks when combining reactions

multiply

at equilibrium

, delta g knot =

-RT ln K (r is gas constant)

you CANNOT say like dissolves like, you must say that the 2 liquids are_

miscible because of certain IMFs

u CANT js say opposites attract, u MUST talk about stuff like _ and _

electrostatic forces and coulombic attraction. because protons are positively charged and electrons are negatively charged they’re going to experience electrostatic forces/ coulombic attraction (talk about distance and magnitude of charges)

as you move from left to right in a period, Zeff _ because there are more protons pulling in their electrons, this greater attraction cause the atomic radius to get _

increase, smaller

the smaller the atomic radius, the greater the _ _between the electrons and the nucleus, and the _ the ionization energy (Energy required to remove an e from gasoues atom/ion)

coulombic attraction & higher

DONT say it, _ the substance

name

if you don’t know what a substance is classified as, call it a _

particle

molecules have _bonds

covalent

formula units are…

ionically bonded substances like NaCl

buffers are a mixture of a _acid/base and its _ base/acid

weak & conjugate

buffer solutions tend to resist pH changes by…

neutralizing / reacting even a strong acid/base

h bonding

FON

microwave radiation causes molecules to…

rotate

infrared radiation causes molecules to…

vibrate

UV / Visible radiation causes electrons to…

to transition to different energy levels or even ionize from the atom

these are soluble in water:

group 1 ions, NH4 + (ammonium), NO 3- (nitrate), acetate (CH3COO-), HCO3-, chlorate (ClO3-)

halides (Cl-, Br-, I-) are insoluble when combined with…

Ag+, Pb2+, Hg 2+ (PbHgAG = PHAg)

delta H =

sum of H bonds broken - sum of H bonds formed (reactants - products)

dilution acid/base equation

aVM = bVM

tirtration équation

at equalvalence pt, MaVa= MbVb

at half equalvalence pt of a titration…

pH = pKa

percent error =

(calculated- accepted)/accepted times 100

- delta g =

thermodyfav process

positive delta g =

non thermodyfav process

when - delta H and + delta S,

the reaction is TMD favored at all temperatures

when + delta h and - delta s,

never TMD favored

red _& an _

cat & ox

OIL R__

IG = OIL RIG

in galvanic, the CAT gets…

fat (electrode mass increases)

in electrolysis, anode is pos and cathode is neg bc…

external power source forces electrons out of the “anode”, and when electrons leave a speacies, the remaining species becomes + charged. the power source pushes e into cathode, making it neg

salt bridge anions go to …

anode to neutralize the build up of charge in each half cell. As one part of the whole cell loses mass (anode), it means that the solid part is being converted into cations bc it’s losing electrons, so there are more cations, making that part build up positive charge. when anions move to the cathode, it balances out the positive charge

as temp increases greater than 25 celcuis, Kw goes _ , so pH goes _. BUT SOLN STILL NEURTRAL

up & down

at 25 celsius, something is neutral when _ = 7. But AT ALL TEMPS, neutral is when _= _

pH & [H+] = [OH-]

for the 6 strong acids (hi (h)br hcl hi, hno3, h2so4, hclo4), [H+] =

[strong acid]

silicon is a _ solid

network covalent

systems of atoms ions or molecules are typically found in the state that minimize their potential energy, making them more _

stable (bc most of the time that means bonds are formed and therefore it’s exothermic)

metallic character, reactivity of metals, and atomic radius trends all increase…

down and right to left

bond strength has a lot to do with …

charge of the atoms, higher charge should mean stronger bond

as you form 2 or even 3 bonds between 2 atoms…

your increasing the number of shared electrons which increases the atoms’ charges

bond energy is the energy…

absorbed when bond breaks

you can find the pH of the analyte (the bottom flask) by looking at the _ of the tirtation curve

beginning

you can find the pH of the tort rate (the burette) by looking at the _ of the tirtation curve

end

equivalence point is when…

the moles of acid = the moles of base

a MaVa=

b MbVb (a = number of h+ donated, b = number of OH- ions provided)

half equalenvence pt equations work only when _ is present

buffer (weak acid/base and strong base/acid )

At the half-equivalence point: for weak acid tirtrationa…

pH = pKa

At the half-equivalence point for weak base titrations…

• pOH = pKb

at half equilcace pt the concentration of…

conjugate base = [ weak acid]

delta H of a reaction give the amount of heat energy released/absorbed by a chemical reaction at constant_

pressure

if V and T are constant, moles are _ to the partial pressures.

proportional

according to Hendersen-Hasselbalch equation, if the ratio of the [] of the base to that of the conjugate acid is the same in 2 buffers of the same acid, the pH values will be _

the same

delta g (yes/no) indicates the rate of a reaction

no

• At the half-equivalence point, the concentrations of the weak acid (HA) and its conjugate base (A-) are _ ([HA] = [A-]). 

equal

at half equivalence pt [weak acid/base] = [conjugate base/acid], but at equivalence (all of the weak component is neutralized) pt, VM =

VM