CHEM Flashcards
(551 cards)
1
Q
When Cations are formed (loss of electrons) how does the configuration change?
A
Looses outermost (highest n, lowest nrg) electrons first.
-Could result in anoamlous configurations
2
Q
Isoelectronic
A
Same electron configuration
3
Q
Non Metal Characteristics
A
Poor Conductors
Non-Malleable and Brittle
Low BP and MP
4
Q
Electronegativity
A
Attract electrons in covalent bond
Up and Right
5
Q
Effective Nuclear Charge Zeff
A
To the right (and down)
-The effect of protons pulling VE in
-Increases with atomic number and decreases with shells, going down
6
Q
Atomic Radis
A
Distance from the nucleus to the outermost electrons, those who want cat ion give up easy cuz not close to nucelus
Down and Left
7
Q
Lattice Energy
A
The energy required to break up an ionic bond
-Increases with charge and closeness
8
Q
Ionization Energy
A
Minimum energy to remove an electron from a neutral gas atom
-Up and Right
9
Q
The IE is always the highest when
A
Trying to remove a electron from a Nobel as configuration
10
Q
The second IE is always greater than first because?
A
IE is removing a negative charge. Once done it becomes a positive cation, and now you are trying to remove a negative away from a positive.
Gets harder everytime especially once at natural state
11
Q
Electron Affinity
A
Energy released for an electrion is added to neutral gaseous atom
-How much the atom wants a electron
-Up and Right
12
Q
First EA is endothermic or exothermic
A
Exothermic, natural the electron is attract to Zeff
EA Neg
13
Q
Second EA is endothermic or exothermic
A
Endothermic because next electron has to overcome electrostatic repulsions.
EA positive
14
Q
What is the relationship between mass/momentum and wavelength
A
Inverse
15
Q
Heisenburg Uncertainity Principle
A
Exact position and momentum cannot be measured simultaneously
16
Q
What function is used for the photoelectric effect?
A
Work Function
-Minimum energy to release a photon
Ek=Elight-W
17
Q
Metallic Character increases
A
Down and Left
18
Q
Empirical Formula
A
Smallest set of whole numbers that describe ratio of elements in a molecule
19
Q
When a balanced equation only contains 1:1 ratio the limiting reagent is?
A
The one with the least amount of initial moles
20
Q
Cation with a decreased charge have suffix
A
“ous”
21
Q
Cation with a increased charged have suffix
A
“ic”
22
Q
Polyatomic ions with multiple O2 for less amount of O2 have suffix?
A
“ite”
23
Q
Polyatomic ions with multiple O2 for more amount of O2 have suffix?
A
“ate”
24
Q
Increased charge on O2 containing polyatomic ions prefix?
A
“per”
25
Decreased charge for O2 containing polyatomic ions prefix?
"Hypo
26
Binary Acid Naming (H + Nonmetal)
Prefix= Hydro
Suffix = ic
27
Oxyacids Naming More Oxygen suffix
"ic"
28
Oxyacids Naming less Oxygen suffix
"ous"
29
Bond Order
How many bonds in a covalent bond
30
Sigma Bonds are located/formed?
head on overlap of orbitals along the axis between atoms
31
Pie Bonds are Formed?
Side-on overlap or parallel p orbitals
32
Single bonds have ___ sigma and ____pie
1 sigma
33
Double bonds have ___ sigma and ____pie
1 sigma and 1 pie
(1 supper, 1 dessert)
34
Triple bonds have ___ sigma and ____pie
1sigma and 2 pie
(1 supper, 2 desserts)
35
T/F Bonds are stable and decrease PE of system
True
36
Does a higher bond order mean higher or lower strength?
Higher Bond Order
Increased Bond Strength
Increased Energy to Break Bond
Decreased PE
37
Decreased bond length (triple --> Double -->Single) means stronger or weaker?
Stronger
38
Double Bonds can/or cannot rotate?
Cannot,
Two separate molecules even though same formula, ISOMERS
39
Single bonds can/or cannot rotate?
Can,
Same molecule if same forula
40
Sigma bonds are weaker or stronger than Pie
Stronger, ON OWN: but more pie bonds (double or triple) are stronger and more energy to break
41
The central atom is a structure is usally what?
Most EN
(usually carbon)
Halogens are usually terminal
42
What are the 3 exceptions to the octet rule
Incomplete Valence
Expanded Valence
Odd Electron Species
43
Incomplete Valence
Some atoms do not always need a full octet when forming a complete set of covalent bonds
44
Expanded Valences
Some atoms can accommodate more than a full octet when forming a complete set of covalent bonds
(P and Sulpher)
45
How many bonds can P have?
3-5
46
How many bonds can S have?
2-6
47
Odd Electron Species
Some molecules have an odd number of electrons. This makes it impossible for all their atoms to satisfy the octet rule and leads to unpaired electrons
A species with at least one unpaired electron is called a radical.
48
A species with at least one unpaired electron is called
A Radical
49
What is a Oxyacid
Hydrogen, Nonmetal and Oxygen
Hydrogen is directly attached to oxygen not a central atom
50
Resonance structures must have these two things:
1)Same Connectivity
2)Same Overall Charge
51
Major Resonance Structures have these 4 qualifications:
1)Full Octet
2)Minimum number of FC
3)Negative FC on electronic atom
4)Minimum separation between opposite FCs (stabilizes either)
52
Linear Angle
180 (360/2)
(2 attached)
53
Trigonal Planar Angle and attachement
120 (360/3)
(3 attached)
54
Tetrahedral Angle and attachement
109.5
(4 Attached)
55
Trig Bipyramidal Angle and attachement
90 and 120
(5A ttached)
Trigonal Planar + Linear
56
Octahedral Angle and attachment
90
(6 things attached)
3Linear
57
sp number of groups
2
58
SP2 Number of groups
3
59
SP3 Number of groups
4
60
SP4 number of groups
5
61
SP5 Number of groups
6
62
Nitrogen/Oxygen attached to Oxygen that could be double bonded by resonance is what hybridizaton
SP2/ LOOKS SP3
63
If a atom has a choice between SP3 and SP2 is chooses?
SP2
64
Trig planar: SP2 with one lone pair molecular geomtery
bent
65
Tetrahedral: SP3 with one lone pair molecular geometry
trig. pyramidal
66
Tetrahedral: SP3 with two lone pairs molecular geometry
bent
67
lone pairs in molecular result in what to bond angles, Increased repulsion
Decreased bond angles
68
What is Huckles Rule
All aromatic compounds must have odd number of pie bonds
2,6,10, 14.. (up by 4) pie electrons (1 pie bond = 2 pie electrons)
4n + 2Pie Electrons
69
Aromatic compounds must be ____ hybridized
SP2
70
Unsat versus Sat for packing
Sat.
Unsat = Pie bonds= rigid, and cis is even worse (Can't tangle)
Sat= Sigma bonds and no cis and trans so it can tangle (take more to freeze when tangled)
71
What is Chirality
Any object that cannot be superimposable on its mirror image
Chiral centers have four different atoms or groups attached
72
D-Glucose
GUN
O ontop
Oh R
OH left GUN
OH R
OH R
OH R
CH2OH on Bottom
73
Constitutional Isomer
Same structure (ATOMS) different connectivity
74
Steroisomer
Same atomic connectivity but a different arrangement in space.
75
Conformational Isomer
They have the same molecular formula and connectivity, but their structure differs by the rotation of their carbon-carbon single bonds.
NEWMAN PROJECTIONS
76
What is the most stable Newman projection configuration?
ANTI: Staggered
LOW TEMP.
gauche are also staggered but carbon groups are closer not exactly 180 apart
77
What is the least stable Newman Projection configuration?
Eclipse
Overlappig especially when the carbon groups are
78
Z Priority
High Priority groups same side
79
E Priority
High-priority groups on opposite side
80
Enatiomers`
A pair of molecules that have the same connectivity but the opposite configuration at every chiral center
-Non -super impose mirror images
-Mirror image but cannot be placed on top of another
81
How do enatiomers act in plan polarized light?
They have the same properties
BUT ROTATE Opposite in Plane polarized light; but equal in quantity
82
5 Characteristics of Enatiomers
1)Opposite stereochemistry at all chiral centers
2)Identical physical properties
3)React identically in most enviro
4)React differently in a chiral envrio
5)Rotate opposite in plane-polarized light
SEE BEST OF FISCHER
83
R absolute stereochemistry is what direction?
Clockwise
84
S absolute stereochemistry is what direction?
Counter Clock
85
Absolute configuration when H is in not front (SIDES OF FISCHER)
Flip the R/S
86
Absolute configuration when H is in not front (Top and Bottom of Fischer)
Switch both sides and calculate
87
Dextorotatory (+) Rotates plane polarized light what direction?
Right Clockwise
88
Levorotatory (-) Rotates plane polarized light what direction?
Left CC
89
Racemic Mixtures
50% R
50%S
A equal mixture of both the R and S Enatiomer
90
What enantiomer do humans produce naturally
S
91
Racemic Mixture effect plane polarize light how
No net rotation of plane polarized light
92
How are racemic mixture seperated: Resolution of Enatiomers and Chemotology
Enantiomers react with another chiral molecule to produce diasteromic salts
ENATIOMERS CAN ALSO BE SEPERATED BY CHEMOTOLOGY
93
What are Diasteriomers
Stereoisomers that are not mirror images
-At least one different stereocenter and at least one same stereocenter
Opposite formate (L/R) chiral centers from each other in Fischer projection
94
What is the max number of stereoisomers for a molecule
2n
n= number of chiral centers
95
Meso Compound Requirements x2
1)Minimum 2 chiral centers
2)But achiral (have internal plane of symmetry)
96
Meso compounds in fischer projects cut what way for internal plane?
Horizontal (Hamburger)
97
Meso compounds do what to plane polarized light?
Do not rotate as the chiral centers cancer each other out
98
T or F Diasteromers have different physical properties
True
This means that they can be separated by:
Chromatography (polarity)
Distillation (BP)
Extraction (Solubility)
99
Thin Layer Chromatography is used for?
Polarity
100
Gas Chromatography is used for?
Boiling Pts
101
Size-Exclusion Chromatography is used for?
Size
102
Affinity Chromatography is used for?
Affinity
(antibody interaction, receptor-ligand interaction)
103
What are stereospecific reactions?
Reactions are those that only create one kind of enantiomer
PERFECT
104
What are stereoselective reactions?
Reactions favour one type of enantiomer but still have some amount of the other
LOOSE
105
Resolution x3 steps
When the extraction technique separates enantiomers (racemic or other ratio), it is called a resolution.
Enantiomers containing reactive functional groups (acidic or basic site) will react with optically pure compounds (all + or -) to make 2 diastereomers (diastereomeric salts)
Diastereomers can be separated via crystalization (one crystalizes and the other remains soluble)
To restore enantiomer: react the diastereomer salt with something to restore the functional group: Washing with an acid or base too cleave the restoring agent
106
Extraction
Liquid-liquid extraction is the process of separation based on the differing solubilities of compounds in different aqueous and organic solvents
REMEBER LIKE DISOLVES LIKE: will tell you what layer the desired molecule will be
107
How does extraction work
Separatory funnel filled with organic solvent (usually non-polar) containing some mixture of organic compounds to seperate
An Aq solvent is added (acidic, basic or neutral) and mixed
Two phases then allowed to seperate, aq phase is denser and drains
108
Organic Layer of a Liquid-Liquid Extraction will contain?
Non-Polar Molecules,
109
Aq Layer of a Liquid-Liquid Extraction will contain?
Polar Molecules
110
Thin Layer Chromatography TLC
Separates components of a mixtures of compounds by exploiting each compounds differing affinities for the polar STATIONARY HASE and their solubility in the less polar MOBILE PHASE
111
Stationary Phase
Species stuck to the rigid plate
112
Mobile Phase
Solvent which travels up the plate
113
More polar compounds in TLC
More time it will spend adsorbed on the polar coating and slower it will move up plate
114
Less polar compounds in TLC
Spend more time dissolved in relatively non polar mobile phase and will up the plate faser
115
How many stationary phase and are they polar or non-polar
2
Polar, More polar than any solvent you use as a mobile phase
116
Changing the polarity of the mobile phase will do what
Change the distance each component travels (increasing = increases, proptional relationship)
-Not change elution order
117
How to compare samples between trials of TLC
Retention Factors
Rf= Distance compound (product) travelled/Distance traveled by solvent (reactant)
Left= Reactant
Right= Product
AT TOP and END of RXN, there should be nothing right top as it is turned reactantr
118
Paper Chromatography
Uses paper as the stationary stage
Compounds solubility in the mobile phase determines its retention factor Rf
Anticipate: Highly soluble compounds travel farther than lower soluble in the solvent system used as a mobile phase
119
Ideal Gas Equation
pv=NRT
120
The average kinetic energy of a gas is proportional to what?
Temperature
121
How to measure atm pressure using a barometer?
Patm = pgh
-p = density of mecury
-g =gravity
-h= height of mercury
121
How to measure pressure of a unknown gas using a manometer?
Psam = Patm + pgh
-p atm must be known
-p is density of gas
-h is the height of liquid above point B (for sample) or A (for atm)
Patm =Psam +pgh
122
How many kpa is 1 atm of pressure
101kpa
you are 1 atm
lol kpa
123
How many bar is 1 atm of pressure?
1 bar
124
How many torr/mmHg is 1 atm of pressure?
760 Torr
760 mmHg
125
At STP 1 MOL of any idea gas is how many L
22.4 L
126
WHAT Temp is STP
274.15 k, 0C
1 ATM
127
What is absolute zero in K and C
0K
-273 C
128
When temperature increases what happens to pressure and volume?
Volume Increases
Pressure Decreases
Proportional Relationship
129
What is the relationship btwn volume and pressure
Inverse
130
What is the partial pressure of a gas?
The partial pressure of a gas is the same pressure it would exert if it were alone in the container.
131
Partial pressure is proptional to?
Mole fraction
Number moles of gas A /
total moles of gas in container
132
Calculation of partial pressure of a gas?
Pa = Xa x P total
Mole fraction x total pressure
133
True or False all partial pressures add up to the total pressure of the gas in a container?
T
134
For an ideal gas pv/NRT will equal what?
1 atm at any external pressure or temp.
135
A gas is ideal at increased or decreased pressure?
Decreased
136
Why in real gases will PV/nrt deviate from 1 atm
PV is greater than NRT
When P increases, V doesn't decrease proportionally (more resistance to decreases, as gas molecules take up space)
-Therefore, it is ideal to have decreased pressure.
137
When is a real gas PV/NRT (compressaibility) greater than 1?
Positive deviation is due to volume (molecular volume)
138
When is a real gas PV/NRT (compressaibility) less than 1?
Negative deviation due to intermolecular forces
139
At low/moderate pressures, the PV real value will be less or more than the PV ideal?
Less, as the volume as less volume than predicted by ideal gas law
140
At high pressures, the PV real values will be less or more than the PV ideal?
Greater, as the volume is greater than predicted by gas law (restriction to compress)
141
How does temperature effect a real gas compared to ideal?
The higher the temperature the closer to ideal as there is less intermolecular force interaction
142
What is the vanderwalls equation used for?
Un ideal gases
143
n2(a)/V2 part of vanderwalls accounts for
Attraction (interaction/intermolecular forces) between molecules
144
nb terms in vanderwalls accounts for
Bulkiness (volume of particles)
145
How are reaction rates expressed (what unit)?
M/s
146
How to find the reaction rate?
Take the amount of moles and multiple it by stoich ratio
147
Reaction rate decreases with what?
Concentration of reactants
148
T or F: Orders of rate laws can be determined by stoich ratios?
False Must be determined experimentally
149
T or F: Rate law uses both products and reactants?
False just reactants
150
The sum of all the orders is equivalent to what?
overall order of the reaction
151
Rate law equation
R= k[A]^x[B]^x
where x is the orders of each corresponding rectant
152
How to calculate the rate law and rate constant of a reaction?
1) Find orders:
-For each one where one reactant is constant and the other is changing between 2 trials
-(X1/X2)^m = R1/R2 (solve for m)
2) Rearrange R=k[A]^x[B]^x to solve for K
Use randome trial
153
Calculates the units of the rate constant (K)
nth-order
M^(n-1) x S^-1
154
Oth order reaction is what?
Slope = -K
Concentration vs time
Linear down
ntegrated: Linear neg slope down
155
1st order reaction is what?
Slope = -k
ln concentration vs. time
Curve down not as steep
Integrated: Linear neg slope down
156
2nd order reaction is what?
Slope = k
1/concentration vs. time
Curve steep slope down
Integrated: Linear Positive slope up
157
Difference between rate laws and integrated rate laws
Rate laws predict the rate of the reaction from initial concentrations of reactants.
Integrated rate laws predict the reactant (or product) concentration as a function of time.
158
What 3 factors is the rate constant dependant according to the Arrhenius Equation?
p: fraction of collisions with proper alignments
z: collision frequency
f: fraction of collisions with sufficient kinetic energy to overcome the activation energy of reaction
159
What 3 things can effect reaction rates?
1) Reactant concentrations
-increases with increase concentration
2)Temperature
-increases the speed of molecules and collision frequency as temp increases
3)Catalysts
-Raise the reaction rate without being permanently consumed
160
In Endothermic rxn, the energy of the products is greater or less of the reactants?
Greater than the reactants therefore require alot to overcome energy of activation
161
In exothermic rxn, the energy of the products is greater or less of the reactants?
Less than the reactants
therefore give off energy, and do not need to overcome energy of activation.
162
true or false Catalysts are used and then formed.
true
163
true or false intermediates are formed and then used
true
164
What are characteristics or termolecular reactions?
slow or don't happen
165
What is molecularity?
The number of molecules involved in a given elementary rxn
166
When can stoichemetric coeffients be used to determine order?
Elementary reactions
(broken down into it steps, to be sure)
-Unimolecular (dissociations) squared
-Bimolecular
-Trimolecular
167
Equilibrium constant can only be affected by what?
Temperature
168
T or F equilibrium constant includes all states
F, only aq or g
169
If the co-efficients of a balanced equilibrium reaction are multipled by a given factors the equilibrium constant will be?
Taken to the power of that factor
170
If the co-efficients of a balanced equilibrium reaction are divided by a given factors the equilibrium constant will be?
Taken to the root of that given factor.
171
When multiple equilibrium reactions are combined, the equilibrium constants of the reactions are?
Multiplied together.
172
What is the reaction quotient (Q)?
Expression that combines all the instantaneous concentrations or partial pressures in a given system
Gives the rxn current loco at a pt in time.
173
How is Q (reactin quotient) calculated?
Same as equilibroum constant (Kc) Products over reactants using stoich co-efficienrts_
174
Comparing Q to K tells u what?
Direction of the reaction to reach equilibrium
175
If Q is less than K
System is moving towards equilibrium in the forward directions
Q must increase
176
If Q is greater than K
System is moving towards equilibrium in the reverse direction
Q must decrease
177
Increasing volume/decreasing pressure shifts the equilibrium how?
To the one with MORE chemicals
Make more moles cuz space
178
Decreasing volume/decreasing pressure shifts the equilibrium how?
To the one with LESS chemicals
Make less moles cuz less space
179
Exothermic reactions increasing temp, what happens to equilibrium constant K?
Decreases (shifts away from heat) reverse
180
Exothermic reactions decreasing temp, what happens to equilibrium constant K?
Increases (shifts towards heat) forward
181
Endothermic reactions increasing temp, what happens to equilibrium constant K?
Increases (shift away from heat)
Forward
182
Endothermic reactions decreasing temp, what happens to equilibrium constant K?
Decreases (shifts towards heat) reverse
183
What is the general rule for solubility?
Partners of strong acids/bases are soluble
184
What is a Arrhenius acid?
Produces H+ ions in aq
185
What is a Arrhenius base?
Produces OH ions in aq
186
What is always formed in a neutralization rxn?
Salt and Water
187
Bronstead Lowry Acid
Species that produce H+
188
Bronstead Lowry Base
Species that accepts H+
189
Lewis Base
Species that acts as an electron-pair donor
Nucleophile
Bases Loath Electrons
189
Lewis Acid
Species that acts as an electron pair acceptor
Electrophiles
ACIDS LOVE ELECTRONS
190
7 Strong Acids
HCl
HBR
HI
H2SO4
HNO3
HClO3
HClO4
191
8 Strong Bases
NaOH
KOH
CaO
Na2O
H-
Ca(OH)2
Ba(OH)2
Sr(OH)2
First two columns bound to OH
192
Ka and Kb values are used for strong or weak acids or bases
Weak
193
p mean what
-log (x)
194
pH + pOH equals what
14
195
What is Kw
Water equilibrium constant
Keq = [H3O+][OH-]
196
Increasing the teperature does what to pH
Decreases
6 is neutral instead of 7 @ greater the 25C
197
What happens if the concentration of the strong acid is less than 1x10^-7 M (less than the concentration of H+ already in water)
This applies to strong to bases too (less than concentration of OH- already in water)
Negligible
We need to take the autoionization of water into account>?
Pick the answer close to 7 on the right side of neutral
198
True or False a really strong acid can make a weak acid behave like a base
True
Same for bases
(weaker than water)
199
A weak acid reacts with water and gains or looses H+
Looses H+ (becomes conjigate base, more neg)
H3O Produce
weak acid = acid
H2O = Base
200
A weak base reacts with water and gains or looses H+
Gains H+ (Becomes cong acid, more poistive)
OH- produce
Weak Base =Base
H20 = acid
201
What is the relationship bwtn Ka and Kb?
Ka x Kb = 14
The Ka of weak acid, Kb is the conjuygate base
202
If a Ka of a weak acid is greater than 10^-7 the conjugate base will stronger or weaker?
Weaker
203
If the Ka of a weak acid is less than 10^-7 the conjugate base will be stronger or weaker?
Stronger
204
The conjugae to a strong acid or base will be?
VERY WEAK
205
When Ka increases what happens to Pka
Decreases
Ka gets bigger = Stronger
PH= gets smaller (more acidic)
206
Ka/Kb from PKa/PKb
Kb/Ka = 10^-pka/pkb
207
Pka/PkB from Ka/KB
pkb/pka = -log (ka/kb)
208
Ka to Kb
Kb =Kw/Ka
Ka =Kw/Kb
209
Pka to Pkb
Pka =Pkw (14) -Pkb
Pkb = Pkw (14) -Pka
210
When are ice tables used?
When calculating the pH for Aq solutions of weak acids and bases
211
Ice tables how to use?
1) calculate initial molarity C=n/V
2)Make sure rxn balanced
3)make table to find Ka expression
4) Ka expression
Ka= x2/ M-x
5)Removes -x
6) Add in Ka values (given)
7) Solve for x
(usually will have to increase mantas and decrease exponent)
8) Solve for pH
212
Strong Acid + Weak base produce what
Acidic Salt
Cation is acidic and anion is neutral
213
String base + Weak acid produces what
Basic Salt
Cation is neutral and anion is basic
214
A stronger acid produces a more or less stable base?
More stable conj. base
215
What determines the strength of a an acid
ARI
Atomic Radius
Resonance
Induction
216
A stronger acid will have the most ____ atom, and the negative charge will be on that atom in the conjugate base
Electronegative, holds the neg charge better.
Right and Down the PT
Better the closer to the subituant is
217
What are inductive effects and how to the relate to stability?
They spread out charge
The more electroneg atoms the more spread out and mmore stable
218
In a AA the carbonyl group pka is what
2
219
In a AA the amino group pka is what
9
220
For a polyprotic acid the pH of the solution is equal to what?
[H3O+] produced from only the first step (rest are negligible)
-Find the pH from the first step.
221
Pka of D and Isoeletric (when neutral)
4, A: Two smallest
222
Triprotic Amino Acids are?
Charged
223
Pka of E and Isolectric (when Neutral)
4, A: Two smallest
224
Pka of H and Isolectric (when Neutral)
6, B: Two Largest
225
Pka of C and Isolectric (when Neutral)
8, A: Two Smallest
226
Pka of Y and Isolectric (when Neutral)
10, A: Two Smallest
227
Pka of K and Isolectric (when Neutral)
10, B: Two Largest
228
Pka of R and Isolectric (when Neutral)
12, B: Two largest
229
What is a titration?
Adding small amounts of a strong acid or base to determine the unknown solution of a strong acid or base
230
What is the equivalance /Stocihemtric pt?
When all the analyte has been reacted with titrant
For a SA/SB curve = pH 7
231
How to know when the equivalence pt occurs?
Using a indicator (weak acid or base) changes colour at the end point
232
What is the end point of a titration curve?
When the indicator changes colour
233
When does a buffer region occur in a titration?
Titration with a weak acid and strong base.
Equal amount of weak acid and and conj base
Number of moles of weak acid is half of the amount of moles of strong base added.
pH of the solution is pKa of weak acid
233
How to decide what indicator to use?
The one that colour change pKa is during the known equivalance pt (when all analyte has bene reacted with titrant)
234
What is the mid point
half-equivalence point
pKa of the weak acid
235
The buffer region exists in range?
PKa +/- 1 pH unit of 1/2 equivalance pt/mid point /pka of weak acid
236
What is the Henderson Hassalbach Equation?
pH = pKa + log (Conj. Base/ Weak Acid)
For titrations with weak acids and strong bases
Calculates the pH of a buffer solution.
237
How to find how many ions/molecules in a a given amount of moles?
Multiply by avogaardros number 6.02x1023
238
What is a buffer made of?
A weak acid/base and its conjugate in equal concentrations
239
Why is water not inlcuded in equibirum equations
Because it is constant throughout the entire rxn
240
What is thermodynamics?
The study of the flow of energy during the chemical process
241
Extensive Property
Depends on the amount of matter present in a system
-Mass, Volume, Entropy, Enthalpy, Internal Energy, Free Enegry
242
Intensive Property
It does NOT depend on the matter present in a system
-Temp. Density, Melting Pt
243
Thermodynamics: process
Net difference between final and initial states
244
Thermodynamics: Path
Complete series of steps taken to get from initial to final positions
245
What is temperature?
Measure of average kinetic energy per system
246
Zeroth Law of Thermodynamics
When 2 or more objects are brought together, they will exchange energy until they are at the equiibirum (same temperature.)
247
State Functions
Properties that depend on only final and initial states and no the path taken
HAVE CAPITALS
248
Path Function
Are properties of a system that depend on the way in which the change is carried out
LOWER CASE
249
4 Types of Internal Energy Lowest to Highest Energy
1)Translational Energy
2)Rotational Energy
3)Vibrational Energy
4)Electronic Energy
250
What are the two ways to transfer energy
1)Heat
2)Work
251
3 Ways heat is transfered?
1)Conduction (touch)
2)Convention (within fluid)
3)Radiation (EM waves)
252
Free Work is
Positive
(work done to you)
253
Doing Work is
Negative
(work done BY you)
254
What is internal energy
The sum of the kinetic and and potential energy in a system
255
First Law of Thermodynamics
Total energy of the system and surroundings is constant
Change of energy in a system must equal the sum of heat exchanged to/from system and work done on/by the system
255
2 ways to transfer internal energy
1)Heat
2)Work
256
Endothermic
ENEGRY GAINED
Heat is absorbed by System
-q is greater than 0
Work is done on the system
-W is greater than 0
257
Exothermic
ENERGY LOST
Heat is given off from system
-q is less than 0
Work is done BY system
-W is less than 0
258
Enthalpy
Total energy transferred during a chemical process, including the change in internal energy and any energy (work) required to make room within surroundings for the products of the reaction
Joules
259
Hess's Law
The total enthalpy of an overall reaction is equal to the sum of enthalpy changes for he indvidual steps
260
What are the 2 rules of Hess's Law
1)If the stoichiometric co-efficient of a reaction step is multiplied or divided by a factor, then the change in enthalpy for the same step must be multiplied or divided by that same factor
2)If a reaction step is reversed than the sign of the change in enthalpy must also be reversed
261
What is the standard enthalpy of formation?
Enthalpy change that occurs during the formation of ONE mole of a substance from PURE ELEMENTS in their STANDARD STATES
262
What is the standard enthalpy of formation of a pure element in its standard state
0
263
Entropy (S)
State function that provides a quantitative measure of the NUMBER OF MICROSTATES
264
Increased amount of microstates results in what to entropy
Positive
265
Entropy units
J/K
266
5 Key pts of Entropy
1)Entropy Gas >> Liquids> Solids
2)Higher Entropy
3)Large volume >small volume
4)Large molecule > Small Molecule
5)HIGHER MOLES GAS > LOWER MOLES GAS
267
During phase change what occurs to temperature?
Stays constant
268
What is the second law of thermo?
Any spontaneous process increases the entropy of the universe
269
In a reversible process the entropy of the universe equals
0
270
In a irreversible process (spont.) the entropy of the unviverse equals?
Greater than 0
271
What is the third law of thermodynamics?
At 0K, particles in a perfectly ordered crystal have no thermal energy, no motion, and no disorder
272
Reversible versus irresiversable processes in terms of entropy
Reversible = Make equilibrium
Irreversible = Spontaneous,
273
When Gibbs energy is negative, the reaction is spot. or not?
Spont. in direction written
274
When Gibbs energy is pos. The reaction is pos. or not?
Non. Spont. in direction written
(spont. in opposite direvction)
275
Spont./EXO Products higher or lower than reactants
Lower
Gibbs Negative
276
Non.Spon./Endo. Products higher or lower than reactants
Higher
Gibbs Positive
277
Gibbs free energy depends on what?
Change in enthalpy and entropy at constant temp.
278
Non spont reactions can become spont by doing what?
Changing temperature
Temp. is positive but if you change in high enough so entropy is higher than enthakpy
279
Gibbs in a phase change is equal to what?
0
280
During phase changes what breaks?
INTERmolecular Bond
281
Heat is absorbed in what phase changes?
Solid --> Liquid --> Gas
282
Heat is released in what phase changes?
Gas --> Liquid --> Solid
283
Supercritcial Point occurs at
High Temperature and High Pressure
284
Triple Point Occurs at
Low Temp. and Low P
285
Solid to Liquid
Melting
286
L to S
Freezing
287
S to G
Sublimation
288
G to S
Deposition
289
L to G
Vapour
290
G to L
Condenstation
291
What does the line for water between solid and liquid have a negative slope
Water (Ice) in solid is less dense than liquid water
As pressure increases the melting/freezing point decreases
292
Isobaric
Constant pressure
293
Heat of Fusion
Enthalpy change associated with melting
294
Heat of vapourization
Enthalpy associated with boiling
295
Heat of vapouration or Heat of Fusion greater
Heat of Vapourization
-More energy is required to change phse from liquid to gas than from solid to liquid
296
Heat Capacity
How difficult it is to change the material's temperature
297
Change in temperature in a material depends on these 2 things
1)How much heat was added (q)
2)Heat Capacity (C)
298
Sensible Heat
Temperature changing
299
Latent Heat
Phase Change
(Temp. constant)
300
A longer latent heat period means what
More heat is required for phase change
301
What is a calorimeter
Device that measures the energy changes of a given process
302
Coffee Cup Calorimeter
Measures heat required to carry out a given process at CONSTANT PRESSURE
Heat is either absorbed or released by system and transfered or taken by surroundings
Temp. change of surroundings is measured
303
Bomb Calorimeter is always exo or end
Exothermic
304
Difference between coffee cup calorimeter and bomb
Bomb is constant volume
Coffee is constant pressure
305
Bomb Calorimeter is used to calculate?
Heats of Combustion Rxn
CCal must be known
306
For bond enthalpies ensure what?
Equation is BALANCED
307
Simple alcohols release more or less heat?
More Heat
Increased Enthalpy
308
What are electrophiles
Lewis Acids
Accept Electron pairs
309
3 key features of electrophiles
1)Electron withdrawing groups
-connected to EN atom
2) An incomplete octet: Boron
3)Carbocation: positively charged
310
Most common electrophile functional groups? x3
1) Aldehydes
2)Ketones
3)Carboxylic Acids and Derivitives
311
What are nucleophiles?
They donate electron pairs to electrophiles
312
2 structural features of nucelophiles
1)Presence of lone pair electrons
2)Presence of pie bond electrons (multiple bonds)
3)Negative Charge
313
Functional Groups that are nucelophiles?
1)Alcohols
2)Amines
314
SN2 reactions are how many steps?
1
Nucleophile attacks and LG leaves in the same step
315
When there is a chiral carbon in SN1 reactions, what do you need to be aware of?
R and S configuration
Racemic mixtures
316
What order kinetics do SN2 reaction show?
Second order
r=k(substrate)(Nu)
317
SN2 reactions are primarily used for what type of carbons
Methyl or Primary because least steric hinderance
318
SN2 reactions favour strong or weak nucleohiles?
Strong
319
Better nucleophiles are sterically hindered or not? or does it matter?
Not Sterically hindered
(needs to attack easy)
320
SN2 reactions occur in polar or polar aprotic solvents?
Polar Aprotic
(can't form H-Bonds)
321
Polar Aprotic Solvents
Don't contain Hydrogen attached to EN atoms
322
Polar Protic Solvents
Contain Hydrogen attached to EN atoms
323
SN2 favours what type of leaving groups?
Good LG
324
5 Good LG
1)Water
2)I-,Br-, Cl-
3)Acetate
4)-OTs
5)-OMs
325
Common Aprotic Solvents
1)Acetone
2)Ether
3)DMSO
4)DMF
5)THF
6)HMPA
326
A strong nucelophile is more or less stable?
Less Stable: More Reactive
327
ARIO determines what?
Stability of an atoms/base
328
SN1 rxn are how many steps and explain
2 step substitutions
1)LG leaves generate a carbocation intermediate
2)Nucleophile takes the empty P-Orbital
329
SN1 reactions are what order
First Order Kinetics
rate= k(substrate)
Relies on how fast the LG leaves
330
If a atom does not have the correct number of bonds what does it likely identify?
Wrong Number Bonds
331
The most important factors affect SN1 reactions affect the stability of what?
Create stability in the Carbocation
332
What carbons are the strongest electrophiles/substrates for Sn1 reactions?
Tertiary (3 groups off carbons)
-Yield the most stable carbocation on LG
333
SN2 prefer versus SN1 perfer for stability
SN2 prefer least stable
SN1 Prefer most stable
334
The role of the nucleophile for SN1 reactions?
Doesn't matter cuz not rate limiting step
335
The role of the LG for SN1 Reactions?
Good LG is neccessary , depatrue is the RLS
336
What is a good LG
Required for both SN1 and SN2
-Leaves as a neutral molecule or a sable unreactive anion
-SOMETHING THAT WON'T ATTACK THE PRODUCT OF THE RXN
337
What solvent is favoured in SN1 rxns?
Polar Protic because they stabilize the carbocation intermediate
338
If you see a -OH group in solvent is often what type of reaction?
SN1
339
SN1 and rearrangements
Methyl groups or hydrogens will move to a more stable carbocation to make a SN1 reaction work
carbocation from 2 to 3
340
SN2 sterochemistry
Inverted relative configuration
341
Resonance adds to stability increasing what?
Primary, Secondary, Tertiary
Double bonds increase stability by resonance increase original by 1.5
341
-OH is a strong or weak LG
Weak LG
Therefore must be prontation of OH to make into H2O a strong LG
342
Good Leaving groups are _____conjugate bases and ____ nucelophules?
stable conjugate bases
and
poor nucleophiles
342
What are the 3 ways -OH can be made into a good LG
1)Protonated (made into H2o)
2)Tosylation (R-OTs)
3)Mesylate (R-OMs)
343
Ethers are reactive or not
Not
344
When ethers react they often do with what and how
Substitution reactions with HBr of HI
Any mineral attached to Hydrogen
345
True of False Ethers hydrogen bond
True
346
Why don't ethers bind together
Creates a lower boiling pt then most alcs
347
Is a carbonyl group?
A functional group composed of carbon atoms and double-bonded oxygen atom
348
The carbon in carbonyl compounds has what hybridization?
SP2
349
What reactions do aldehydes and ketones undergo?
Nuceleophillic Addition
350
T or FNucelophillic addition forms racemic mixtures?
T cuz carbocation can attach to either
IF CHIRAL CENTER IS FORMED
351
What is the common carbon-carbon bond created by the nucelophilic addition reaction of aldehyde or ketone?
Cyanohidrin
N triple bond C attaches to aldehyde or ketone with a Hydrogen to remove negative charge on oxygen
352
What is oxidation?
When a carbon gains Oxygens and Looses Hydrogen
353
What is reduction
When a carbon looses Oxygen and Gains Hydrogen
354
When a primary alc is oxidized initially it becomes what?
Aldehyde
355
After a primary alc becomes a aldhyde what occurs using most reagents
Continues oxydation to become a carboxylic acid
356
What reagent stops is used to oxydize a primary alc to just a aldhyde
PCC
357
Most oxydizing agents are
a metal with lots of oxygen
358
Oxydation of secondary alc forms what
Ketones
359
Tollens reagents do what
Oxydize aldehyde to carboxylic acid even in presence of alc
360
Jones reagent do what
Oxydize primary alc all the way to carboxylic acid
361
The number of what determines the amount of oxidation rounds that can occur?
Amount of hydrogen attached to carbon beccause that is what O attaches to (to carbon)
362
What oxidating agents will oxidize a secondary alc
All but Tollens
363
Oxidation of a secondary alc can occur how many times?
Only Once
364
True or False Oxidation of tertiary alc is possible?
False, No hydrogen to loose
365
What reduces aldehydes and ketones?
NaBH4 (sodium borohydride) /Ethanol (EtOH)
+ an acid (H3O+) to yield primary and secondary alc
366
What are carboxylic acids and. esters reduced by?
LiAIH4 (Lithium Aluminium Hydride) /Et2O (Ether)
367
Reduction results in the removal of what
Double bonded O and replace with OH
368
When a ketone or aldyde reacts with a alc what does it form
1 alc: Hemiacetal or Hemiketal
2 alc: Acetal or Ketal
368
When a weak nucleophile (water) adds to a aldhyde or ketone what does it form
Hydrate
369
Nucelophillic additions to ketone or aldehyde work best with what
Acid Catakyst
370
Eliminations cause what to form
Double Bonds
371
What can be used as protecting groups and why
Ketals and Acetaks
Unreactive towards bases
372
Why do we use protecting groups
Because some reagents will oxidize or reduce something all the way and we may not want that
373
What are tautomers
Pair of easily converted constitutional isomers
Interconversion = Tautomerization
374
What are 2 common tautomers
Enol and Keto
375
For simple carbonyl compounds what tautomer is more common?
Keto
376
B-dicaronyl compounds what
tautomer is more common?
Enol Tautomer
Stabilized by Hydrogen bond
377
Tautomerization is best shown by
Shift of hydrogen atom and double bond
378
What are alpha hydrogens
Hydrogens attached to the alpha carbon
379
What is the alpha carbon
The one attached to the functional group
380
What Hydrogens on a molecule are acidic
Only the ones attached to alpha carbon
381
What are enolate anions
When hydrogen can be easily removed from carbon due to resonance stabilization
382
Alpha carbocations resulting enotate anion is possible in what
Ketones
Aldehydes
a-Carbon looses a hydrogen and the double bond from the functional group comes down to stabilize
383
What are the 2 ways a enolate anion can accept a proton
1)Accept in its carbocation form resulting in a ketone
2)Accept in its enolate form resulting in an enol
384
The enol form is chiral or achiral
achiral
385
The keto form is chiral or achiral
chiral
386
If a alpha carbon is chiral when alpha carbon are removed to form enolate carbon what happens
Forms a racemic mixture on return from enol to keto
387
enol versus ketone
Enol = Double bonds btwn and OH
Ketone= Double bond O and 2 H
388
True or False enolate anions can acts as a nucleophile and attack electrophile
true
Negative charge allows them to attack where the Hydrogen was
Beta-Catalyaed alpha subsitution
389
What is an adol reaction
Enolate ion of an aldehyde or ketone reacts with carbonyl group of an aldehyde or ketone
New carbon carbon bond form attaches the 2
OH and Double Bond O is produced
390
What is the best way to predict the products for adol reactions
Landmark (added onto new carbon)
New carbon is between:
OH and Double Bond O is produced
391
What occurs in adol condensation
Looses the OH molecule and gains a double bond between OH and double bond O w
392
When will a adol undergo dehyration?
1)Final step includes acid and heat
2)Final step includes a base and heat
393
What is nucelar magnetic resonance (NMR)
Structure of a molecule based on the different environments of certain atoms
394
Hydrogen Enviroments
Each peak represents a set of chemically equivalent hydrogen nuclei
-Distance away from fxnal group matters
395
On NMR there is a signal peak where
0ppm
396
Signals upfield (higher number) are what?
More e defiecent, heavily shielder
Close to Fxnal group
397
Signal fields downfield (lower number) are what?
Less e deficient, less shielder
Further from final group
398
What is peak splitting
Results in higher number of peaks than on its own, if neighbouring hydrogens are not equivilant
Yours is 1 + # of neighbouring (neigbouring is how many hydrogen come off each neighboruing carbon)
ONLY IF NEIGHBOUR IS DIFFERENT
399
Peak areas or intergral face is represented by
Number of chemically equivalent hydrogems
400
What is the index of hydrogen deficiency (IHD)
Degrees Unsat.
401
In NMR the number of peaks equal
The number of different H Groups
402
Hydrogen enviroments can be told be what in NMR
Number of peaks
403
Electron Polarization can be told what in NMR
Order of peaks(downfield to upfield)
404
Neigbouring Hydrogens can be tild by what in NMR
Number of peaks in each signal
405
Number of hydrogens can be told by what in NMR
Peak Areas
406
IR spectroscopy is used for
Uses EMR from infrared region,
-Bond vibrating at different frequencies when exposed
-Determine Fxnal Groups
407
Vibrations in IR spect are stronger when/increase frequency x2
1)Stronger Bond (T > D > S)
2)Lighter Elements
408
Alochol Vibration frequency
3300 cm-1
C-H
O-H
N-H
LIGHTER SO MORE VIBRATION
409
Carbonyl (C DB O) frequency
1725 cm-1
410
What is ultraviolet spectroscopy used for?
The enxtent of Pie comjugation
(alt. single and double bonds)
411
The higher (longer) the wavelength of max absorption in UV spect means what?
greater amount of conjugation
200-400nm
412
What is mass spect
Gives molecular weights and sometimes molecular formula
finds mass/charge ratio
413
Base Peak Mass Spect
Largest peak
Most common and stable cation
-plotted relative to base peak
414
Parent peak Mass Spect
Approx Molecular weight
The rest are isotopes
-Og mass of molecule before bombardment minus 1 electron
415
Size Exclusion Chromtology
Separates and compares particles by size
large travel less distance cuz don't get stuck
small travel more distance cuz can get stuck in gel
416
What is Esterification?
Carboxylic Acid Converted into esters by SN2 or Fisher Esterification Reaction
417
5 Steps of a Nucleophilic Acyl Substitution
1)ID LG
2)ID NU
3)Break Bond to LG
4)Form bond to NU
5) Add or Subtract H+ so FC= O
418
What is a nucleoohilic acyl subituition
A nucleophilic addition plus a elimination
419
Carboxylic Acids and their derivatives often undergo what reaction
Nucleophil acyl subsitution
420
Rings that contain amide are called what
Lactam
421
What rings are most stable
5 and 6 membered rings
422
What are the 4 carboxylic acid derivitives
1)Acid Chloride
2)Anhydride
3)Ester
4)Amide
423
Acid chloride + Carboxylate produce what
Anhydride
424
Acid Chloride + Alc + Non-nucelophillic base produce
Ester
425
Acid Chloride + Amine produce
Amine
426
How are acid anhydrides produced?
2 Carboxylic acids + Heat
427
What is transesterification?
The process of reacting an ester with an alcohol to yield a new ester and alc.
(Interchange of R-Groups of Reactants)
428
What is sponification?
Hydrolysis of an ester in basic solution
429
How can amides be prepared?
By all acid derivitives
amine + carboxylic acid derivitive
430
To bring a carboxylic acid deritive back to a carboyxlic acid what needs to be done?
React derivitive with water
431
Primary amines react with aldhydes and ketones in the presence of an acid catalyst to yeild what?
Imines
432
Alcohols react with SOCl2 to produce what
alkyl chloride
(same with PCl5 and PCl3)
433
Oligosacchardies are complex or simple polysaccahrdies?
Neither
3-10 units
434
Open chain or linear forms of monosaccharides are classified as x2
1)Aldoses
2)Ketoses
435
What is the suffix of a carbohydrate?
-ose
436
The highest priority group on a fischer projecton is located where?
As close to the top as possible
-Most oxidized functional group
437
Most naturally occuring sugars are D or L
D
438
Enatiomers
Opposite at all Chiral Centers
439
Diastereomers
Some not different at chiral centers
440
Epimers
Only 1 Chiral Center is different
441
Aldehydes and Ketones react with alcohols to produce what
Hemiacetal
Hemiketal
-Nucelophillic addition
442
Axial Position
Above Ring or Below Ring
443
Equatorial Position
In the plane of ring
444
What is more stable pyroanose or furanose
Pyranose (6 membered ring)
comes from 6th (last carbon) Glucose
Furanose (5 Membered ring) Comes from 5th carbon
Fructose
445
What is a anomeric carbon
Only carbon with 2 oxygen groups attache dto iy
446
What is mutarotation
Occurs as the alpha and beta anomers interconvert
447
What is more stable being alpha (trans) both axial or being beta (cis) one axial and one equatorial
Beta One axial one equatorial
Equatorial is most stable
448
Anomers differ how
the highest priority in cis or trans
449
Acetals are formed from what
Aldehydes (2 alc)
450
Ketals are formed from what
Ketones (2 alcs)
451
In a hemicetal/ketal the carbon is bound to what
-OH and -OR
After one alc
452
In a acetal and ketal the carbon is bound to what
2-OR groups
after.2 alc
453
True or False Glycosides are in equilibrium between cyclic and open chain forms
False, they are locked in place in basic and neutral conditions
only acidic can they be brought back to free monosaccaride (hydrolysis , water and catalyst)
454
How to tell if a tollens test occured
Ag(s) produced
455
Aldehydes in open chain form of aldose canreact with what reagents to become a oxidized sugar
Tollens reagent
Benedicts Reagent
456
What are the 3 reducing sugars
1)Monosaccharides Aldoses (Open-chain or hemoacetals)
2)Monosaccharides Ketoses (if they can tautomerize into aldose)
3)Disaccarides or Oligiosaccahrides with hemiacetals or hemiketals (-OH on anomerical carbon)
457
Non Reducing Sugars are?
Acetals and Ketals
458
What is Tautomerization
Additon or removal of H
459
Amino acids are naturally occuring in R or S
S
460
The D or L AA are deterimined by what
Which side the NH2 (amino) group is on
-Flips with H
461
What AA is naturally occuring D or L
L and alpha
462
At what PH are non-charged AA neutral
pH=6
463
What are the two ways AA are formed?
Gabriel Synthesis (Potassium+Diethyl Ether)
Strecker Synthesis (Uses HCN)
464
What is Strecker Synthesis
CN attacks aldehyde , followed by an attack by H2O
Nitrogen removed and COOH formed
465
The formation of a peptide bond bwtn AA is what type of reaction?
Dehydration
466
The formation of a disulfide bond betwen cystines oxidizes or reduces it
Oxidizes
467
How does a double bond effect melting point?
Decreases MP
468
Lipids are soluble in polar or non-polar solutions
Non-Polar
469
How are Terpenes Constructed
Constructed fro 5-Carbon Isoprene units, with atleast 1 double bond
(divisible by 5)
470
Terpenes are what marcomolecule
Lipids
471
Kinetic CTRL favours what 3 things?
1. Low Temp.
2. Short Rxn Time
3. Less Stable Product
472
Thermodynamic Ctrl favours what 3 things?
1. High Temp.
2. Long Rxn Time
3. More Stable Product
473
The double bonds on a kinetic enolate will be where?
One Ends (primary)
Shorter Rxn Time: Means the Ha is easily accesible
Less Sub. Double Bonds = Less Stable
474
The double bonds on a thermodynamic enolate will be where
In middle/btwn (secondary
More Sub. Double Bonds = More Stable
Longer Reaction Time cuz HB is sterically indered
475
How to ensure Kinetic Enolate is formed
1)Use Large Powerful Base (LDA)
2)Low Temp.
-Trap and irreversibly form Kinetic Enolate
476
How to ensure Thermodynamic Enolate is formed?
1)USe Small and Weak Nase (OEt)
2)High Temp
Establishes a equilibrium between all 3 structures favours the more stable thermo enolate
477
Compare the energy diagrams for kinetic and theromdynamic enolate
Kinetic:
-Lower Ea (Lower hump)
-Higher energy product (more reactive, less stable)
Thermo:
-Higher Ea (Higher Hump)
-Lower energy product (less reactive, more stable)
478
What is a solution?
homogenous mixture of two or more solvents, composed of solutes(s) dissolved in a solvent
479
How do like (polar and polar/ non-polar and non-polar) dissolve/interat with eachother
Breaking solvent-solvent intermolecular bonds to form solute-solvent intermolecular bonds
480
What is solvation/hydration
When an ionic compound is dissolved in a solvent it dissociates into ions that are surrounded by the polar solvent
481
When a compound is hydrated what phase does it exist in?
Aq
482
Electrolyte
any ion that can by hydrated
483
What is Molar Solubility?
Moles per litre that can dissolve based on the concentration of product ions
484
Normality
Gram equivalent weight of solute per meter but take stoich ratios into account
Molarity of compound x stoich ratio
485
What is vapour pressure?
The pressure exerted by a gas in equilibrium with its condensed phase (liquid phase)
-The amount of evaporation
486
When has dynamic equilibrium been established in terms of vapour pressure?
When evaporation = condensation
(when molecules in gas phase equal the molecules in liquid phase
487
The vapour pressure of a liquid depends on what?
Temperature
488
Increasing temperature has what effect on vapour pressure
Increased temp. = increased vaour pressure
Positive correlated
489
When does the boiling pt occur in terms of vapour pressure
Vapour Pressure = external pressure acting on the surface of a liquid
490
If a molecule has a high vapour pressure compared to another that same temperature it means it evaporates more or less easily?
Easily Evaporates
491
A molecule with more intermolecular forces will have a lower or higher vapour pressure at a certain temperatuer
lower vapour peressure
Intermolecular forces require high temp to dissosciated (require higher KE)
492
Increased amount of intermolecular forces effect vapour pressure how?
Decreased
493
What is the normal BP?
For any liquid: the temperature at which its vapour pressure is equal to ATM pressure (1 atm)
494
Bond breaking is endothermic or exothermic
Endothermic
495
Bond formation is endothermic or exothermic
Exothermic
496
If the overall enthalpy change in a solution is negative what does it mean about the strength/stability of the new solution compared to the old solution
More stable/strong intermolecular bonds between solute-solvent than the orginal
Energy is lost from the system
497
What is a non-volatile solute
No Vapour Pressure
NaCl
Glucose
Urea
498
What is the effect of a non-volatile solute on solvent-solvent interactions?
Disrupt the solvent-solvent interaction by forming stronger solute-solvent interactions
DECREASING EVAPORATION
499
What is the effect of a non-volatile solute on vapour pressure of the liquid at all temperature?
decreases vapour pressure
Higher Boiling Point
500
What occurs to a vapour pressure curve in response to an addition to a non-volatile solution
Downards and To Right
DEcreased pressure and increased boiing point
501
What are the 2 major effects of a non-volatile solute on a solution of all temperature?
Increased Boiling Point
Decreased Vapour Pressure
502
What is Raoults Law
Change in vapour pressure of an ideal liquid upon addition of a non-volatile solute
503
AMMONIUM
NH4+
504
H3O+
HYDRONIUM
505
OH-
HYDROXIDE
506
CN-
CYANIDE
507
CO3(2-)
CARBONATE
508
HCO3(2-)
BICARBONATE
509
CH3CO2-
ACETATE
510
C2O4(2-)
OXALATE
511
NO2-
NITRATE
512
SO4(2-)
SULFATE
513
PO4(3-)
PHOSPHATE
514
Solubility of GASES increases or decreases with increasing temperature
decreases
515
Solubility of salt in liquid increases or decreases with increasing temperature
increases
516
When calculating oxidation numbers what to do with double bonds?
They count as there own
517
3 Rules for assigning oxidation numbers?
1)Oxidation number of any molecule/ion/atom adds to its charge
2)Consider the charge that the elements want
3)Consider EN/#E
-More EN will take the negative charge
-It can only go with the amount of electrons possible
518
How to solve redox reactions
1)Separate the reaction into ions (half reactions)
2)Balance the half reactions
-Add H2O or H or OH
3)Balance the charges for the half reaction by adding electrons
4)Balance the entire reaction charge (multiply each half reaction by the entire thing)
5)Add the half reactions together (Electrons should cancel)
519
True or False there should be electrons in a balance redox reaction
False, NO ELECTRONS
520
REDOX rxn how to balance oxygen and hydrogen atoms of half reaction in acidic solution?
H2O to balance any Oxygen
H+ to balance any H Atoms
521
REDOX rxn how to balance oxygen and hydrogen atoms of half reaction in basic solution?
OH- to balance oxygen
H+ to balance any H atoms
522
What is a reaction potential
How much the rxn wants to go
523
Standard potential is often given as reduction or oxidation potential
Reduction
(flip sign to make it oxidation)
524
The standard redox is equal to the
cell voltage
525
The anode in a electrochemical cell is where oxidation or reduction occurs
Oxidation (loos e)
-contains reducing agent
526
The cathode in a electrochemical cell is where oxidation or reduction occurs
reduction (gain e)
-contains oxidation agent
527
Galvanic/Voltage Cells are spont. or non-spont
Spontaneous
528
Electrolytic cells are spont. or non. spont
Non-Spontaneous
(have to push electrons towards negative side, then released to positive side)
529
Galvanic/Voltalic Cells produce or require energy
Produce energy and electric current
530
Electrolytic cells produce or require energy
Require energy/ need energy to be supplied to drive the reaction
531
Galvanic cells the anion is ____ and the cathode is _____
Anion is negative
Cathode is positive
532
Electrolytic cells the anion is ______ and the cathode is _______
Anion in positive
Cathode is negative
Electrons go in the wrong direction
533
Electrons always travel which way n a electrolytic cell
Anode to Cathode
534
Good guess for electrochemical cells when running out of time of the side of anode and cathode
Anode is L
Cathode is R
535
Current in a electrolytic cell moves in what direction
Opposite to electron flow
cathode to anode
536
What does a salt bridge do?
Disipates the resulting charge in the anode and cathode by release either a positive or negative charge (opposite to what the side is releasing) making it neutral
ex.
Zn releases Zn2+ therefore SO42- in salt bridges neutralizes the 2+ charge with a 2- charge
537
What are the 2 faradays laws of electrolysis?
1)Mass of material at an electrode from electrolysis is directly propotional to the amount of electricity being transferred
2)Equivalant amounts of electricity will produce different amounts of material proportional to the materials weight
538
What is voltaic cell
A electrochemical cell that uses the same reactants and products at the anode and cathode, but DIFFERENT CONCENTRATIONS to allow a potential to be generated
539
In a voltaic cell the reactants will have a higher or lower concentration
HIGHER concentration
540
Decreased KSP means more or less is dissolved
LESS
541
Increased binding is associated with a high or low K value
high K Value
542
Explain how a galvanic voltanic cell works
1) Anode is oxidized (electrons are released)
2)Electrons travel towards cathode
3)Current moves in direction towards opposite electrons (towards anode)
4)Electrons reduce the cathode
5) Salt bridge dissipate charges gradient
543
In the cathode what reaction occurs
Reduction
The aquous soution gains electron and forms a solid
Cu2+ + 2e- = Cu(s)
Partcipate formed
544
In the anode what reaction occurs
Oxidation
The solid looses electrons into its aq solution
Zn(s) --> Zn2+ + 2e-
