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Flashcards in FINAL Deck (60):
1

colligative property

depends only on the concentrations of particles, not their identities
-boiling point elevation, fp depression, osmotic pressure

2

vapor pressure

proportional to the fraction of its molecules that enter the gas phase
=pressure exerted by gas in equilibrium with its liquid phase at given temp
-increases with increasing temp, increasing entropy, decreased van't Hoff of non vol, and decreased intermolecular forces
-higher VP= more volatile

3

molality

moles solute/ kg solvent

4

henrys law

Cgas= Kh x Pgas

5

entropy trends

increases with increasing micro states, compound complexity, increasing temp, increasing volume, increased number of bonds, g>l>s phases
*****all substance have positive entropies at T>0K

6

2nd law thermo

spontaneous process increases the entropy of the universe

7

Gibbs free energy

maximum energy released by a process occurring at constant temp/ pressure that is available to do work

8

enthalpy

gain or loss of heat as process occurs

9

reaction order

experimentally determined number defining the dependence of the reaction rate on the concentration of a reactant

10

rate law

equation that defines the experimentally determined relationship between reactant concentrations and rate of reaction
m+n=1

11

first order rxn

t1/2 = .693/K
ln[A] x t plot

12

zero rxn

t1/2 = [Ao]/2K
plot [A] x t

13

second order rxn

t1/2 = 1/k[A]
plot 1/[A] x t

14

activation energy

minimum energy of molecular collisions required to break bonds in reactants, leading to formation of products

15

frequency factor (from Arrhenius eq)

product of molecular collisions and expresses the probability that orientation is appropriate

16

reaction rate trend

increased temp= faster
low Ea= large K, fast-forward rxn
high Ea= small K, slow-reverse rxn

17

molecularity

number of ions, atoms, or molecules involved in elementary step** rate law applies to slowest elementary step= RDS

18

catalyst

must be present in beginning of rxn and not consumed

19

manipulating K for reaction rates

Kforward= 1/Kreverse
reaction 1= 1/2(reaction 2).... K1= (K2)^.5

20

Change in free energy versus K

DG<0 = K>1 = product favored
DG>0 = K<1 =reactant favored
DG=0 and K=1 = equilibrium ***

21

enthalpy with spontaneity

DH>0 = endothermic DH<0 = exothermic

22

strong acids

HCl, HBr, HI, HNO3, HClO4, H2SO4
Ka>1****

23

weak acids

acetic, formic (-COOH), HF, HClO, HNO2
Ka<1

24

strong bases

hydroxides of groups1 and 2
LiOH, NaOH, KOH, Ca(OH)2, Ba(OH)2, Sr(OH)2

25

weak bases

nitrogen containing compounds
NH3

26

acid strength trends

increases with:
-increased #oxygen
-increased electronegativity in HXO config.
-decreased electronegativity (increased atomic radius) with HX configuration

27

HA and B

when HA ionizes= A- (conjugate base)
when B ionizes = HB+ (conj acid)
Kb= A- -> HA + OH-
Ka= HA -> A- + H+
neutral: [H3O+]=[OH-] =1x10^-7
kw=Ka x Kb

28

salt solution acidity

anions come from acids (Cl- =conj base)
cations from bases (Na+ = conj acid)
whichever is from the stronger acid or base determines the pH of the salt

29

common ion effect

shift in position of equilibrium caused by the addition of an ion taking part in the reaction

30

acid base buffer

contains weak acid with conjugate base, and then weak base with conj acid... resists changes in pH

31

midpoint

[HA]=[A-] and pH=pKa

32

formation constant

used to calculate equilibrium concentration of free metal ions in solution of complex ions
increased metal charge= increased Ka= increased acid strength

33

lattice energy trends

increased charge= increased LE
decreased size= increased LE
MgO>NaF but NaF> NaCl

34

solubility

g/100mL

35

molar solubility

moles/L

36

molar solubility

uses s(2s)^2.. in M

37

Q and Ksp

Q>Ksp = precipitate will form (reactant favored)
Q

38

voltaic cell

DG<0 spontaneous.. work on surround
potential of voltaic cell approaches 0 as rxn approaches equilibrium... ***at equilibrium Ecell=0 and Q=K

39

electrolytic cell

non spon, does work on system

40

anode v cathode

anode = Lower conc (for conc cell) or lower Ecell
[anode]/[cathode] = Q*******

41

polarity with functional groups

amide>carboxylic> alcohol>ketone- aldehyde> amine >ester> ether> alkynes >alkenes> alkanes

42

alkanes

single bonds, saturated

43

alkenes

R-CH=CH-R

44

alkynes

R-C=C-R

45

ether

R-O-R

46

ester

R-C=O -OR

47

amine

R-NH2 basic

48

aldehyde

R'=H R-C=O -H

49

ketone

R-C=O-R'

50

alcohol

R-C-OH

51

carboxylic acids

R-COOH

52

amide

O=C-N-H (carboxylic+amine=peptide bond)

53

VP trends

increases with decreased IMFs, decreased I, increased T, increased S, decreased non-vol solutes
increased VP= decreased BP, increases FP, decreased particles (non vol)
*higher VP= more volatile

54

misc

-no buffer at equiv point
-strong acids do NOT have higher concentration than weak acids
-strong acids are ionized to greater extent and have lower pH than weak

55

volume on equilibrium

decreased volume= shift to side that has fewer moles of gas
increased volume= shift to side that has more moles of gas

56

trans vs cis isomers

trans: H and R pairs on opposite sides(HR-HR)
cis: H and R on same sides (resp.: HH-RR)

57

strong vs weak acid

a strong acid does NOT have a higher concentration than weak it acid.. it does have a lower pH and is ionized to a greater extent

58

spontaneous process

entropy of the universe increases

59

enthalpy of vaporization

positive delta H

60

adding non vol solute

decreases freezing point, increases boiling point, and decreases VP