Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Chem 112 > Exam Review > Flashcards

Exam Review Flashcards

(52 cards)

Start Studying
1
Q

delta H and spontaneity

A

H +ve- endothermic and non-spontaneous

H-ve - exothermic and spontaneous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Gibbs energy

A

free energy of a reaction, indicates spontaneity
-ve delta G mean spontaneous(favours products)
+ve delta G means non spontaneous(favours reactants)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

entropy (S)

A

thermodynamic property related to energy configurations
- greater entropy means greater number of configurations(increase in disorder)
positive entropy means spontaneous
negative entropy means non-spontaneous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

3rd law of thermodynamics

A

the entropy of a pure perfect crystal at 0K is 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

2nd law of thermodynamics

A

all spontaneous processes produce an increase in the entropy of the universe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

physical vs chemical equilibrium

A

physical equilibrium: equilibrium of a substance from one phase to another
chemical equilibrium: equilibrium of 2 substances(reactants and products)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

at equilibrium concentrations become _____________ and rates become _____________

A

constant, equal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Large K means _______

Small K means _______

A
  • reaction strongly tends to go to completion(alot of products)
  • reaction strongly does not tend to go to occur (alot of reactants)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which way will the rxn shift when:
QK
Q=K

A
  • to the right
  • to the left
  • at equilibrium, no change
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Le Chatelier’s Principle

A

a equilibrium is a dynamic system that can respond to change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which way does the rxn shift
- increasing conc of starting materials
increasing conc of products

A
  • shifts towards products

- shifts towards reactants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Pressure and volume effect

  • reducing volume(increasing pressure)
  • increasing volume (reducing pressure)
A
  • shifts towards direction with fewer mols of gas

- shifts towards direction that produces more moles of gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Temperature effect on equilibrium

  • increasing temperature
  • decreasing temperature
A
  • shifts towards direction of endothermic reaction

- shifts towards direction of exothermic reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Arrhenius theory of acids and bases

A

when dissolved in water, acids produce H+ ions

when dissolved in water, bases produce OH- ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Bronsted-Lowry Theory of acids and bases

A
  • acids are proton donors and protonate water
  • bases are proton acceptors and deprotonate water
  • conjugate acid base pairs differ by one H+
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Lewis theory of acids and bases

A
  • a lewis acid is an electron pair acceptor(electrophile)

- a lewis base is an electron pair donor(nucleophile)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

amount of ionization of an acids depends on (2)

A
  1. initial concentration of the acid

2. the value of the ionization constant (Ka)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

3 rules to predict acids/bases

A
  1. metal ions with a 1+ or 2+ charge do not affect pH(metal ions with a >+2 charge can act as an acid
  2. polyatomic cations in water often act as acids
  3. many anions in water will act as a base
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What determines acid strength

A
  1. electronegativity of neighbouring atoms

2. stability of the conjugate base(delocalization/resonance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What determines base strength

A
  1. electronegativity of neighbouring atoms
  2. stability of the conjugate acid
  3. substituent groups on N
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Common ion effect

Study These Flashcards
A
  • ionization of a weak acid is suppressed by its conjugate base or a strong acid
  • ionization of a weak base is suppressed by its conjugate acid or a strong base
22
Q

Buffer solutions

Study These Flashcards
A

have the ability to neutralize a small amount of strong acid or strong base

23
Q

saturated solution

Study These Flashcards
A

no more solute can dissolve at a given temperature

24
Q

unsaturated solution

Study These Flashcards
A

the solute can fully dissolve in a solution and more solute can dissolve

25
supersaturated solution
has an excess of solute(higher than saturation point) | solution is unstable and will begin to precipitate
26
common ion effect in solubility
the solubility of a slightly soluble ionic compound is lowered in the presence of a common ion
27
Limitations of the Ksp concept
1. limited to slightly soluble salts 2. uncommon ion effect(uncommon ions increase solubility) 3. Ksp assumes complete dissociation
28
Predicting precipitation Q>K Q=K Q
- Precipitation should occur"supersaturated" - solution is saturated - precipitation cannot occur "unsaturated"
29
redox reactions
a reaction consisting of oxidation and reduction half reactions - oxidation is loss, reduction is gain
30
Balancing redox reactions
1. write half reactions and balance those 2. balance O atoms using H20 3. balance H atoms using H+ 4. balance charge with electrons 5. balance # of electrons
31
electrochemical cells vs electrolytic cells
electrochemical cells- if the reaction is spontaneous, electricity will be generated electrolytic cells- if the reaction is non-spontaneous, it can be forced to happen with an external source
32
electrochemical cell conventions
oxidation occurs at the anode | reduction occurs at the cathode
33
standard cell potential
voltage due to a spontaneous redox reaction that forces electrons into motion
34
standard reduction potential
the potential at each half cell
35
cell potentials and spontaneity Ecell>0 Ecell=0 Ecell<0
- reaction proceeds spontaneously as written - reaction is at equilibrium - reaction proceeds in the reverse direction spontaneously
36
``` Batteries Primary cells: Secondary cells: Reserve batteries: Flow batteries and fuel cells: ```
- non reversible, non rechargeable - can be reversed, rechargeable - designed for long term storage or delivering high power over a short time - can be run indefinitely
37
reactions occur at _________
functional groups
38
Nucleophiles and Electrophiles
- can cause bonds to form and break | nucleophiles transfer electrons to electrophiles
39
steps to analyzing a reaction mechanism
1. Housekeeping - redraw starting materials, number relevant atoms 2. Find reactivity - determines bonds formed and broken identify the nucleophile and electrophile 3. Draw mechanisms/ draw the product - draw curved arrows/ interpret curved arrows - check that formal charges, atoms, and total charge are conserved
40
types of reactions: | Acid-Base Proton Exchange
- a proton is exchanged in a reversible reaction | - nucleophile (e donor) acts as a base
41
nucleophile addition to a carbon double bonded to an oxygen
double bond is broken, Nu single bonds to carbon, oxygen is now single bonded not double bonded
42
Reactivity can be influenced by | 5
1. Electronegativity 2. Induction 3. Atom size 4. Electron delocalization 5. Steric hindrance
43
Role of electronegativity on electrophilicity
- electronegative elements pull electron density towards them so greater electronegativity makes better electrophiles
44
role of induction on electrophilicity
greater electronegativity of R group, greater electrophilicity
45
role of atom size on electrophilicty
larger atoms are able to disperse negative charge over a larger area so they are a worse electrophile and a better nucleophile
46
role of electron delocalization on electrophilicity
electron delocalization creates multiple sites of reactivity(resonance structures) so it stabilizes the molecule - increasing electron delocalization(having more resonance structures) increases electrophilicity
47
role of steric hindrance on electrophilicity
greater bulkiness of R group means more hindrance and less electrophilicity
48
What factors control reaction rate (3)
1. Concentration: greater conc, more molecules to collide 2. temperature: increased temperature, more molecules at a higher kinetic energy 3. Molecular structure: molecules must collide at their reactive sites
49
rate constant
- proportionality constant that relates concentrations and orders to the observed rate - larger k value means faster reaction - overall reaction order determines units for k
50
overall reaction order of 0
- sum of exponents=0 - rate is constant throughout rxn - units of k same as unit for rate M/s
51
overall first order reaction
- sum of exponents equals 1 - rate changes throughout rxn as concentration changes - units of k is 1/s
52
overall second order reaction
- sum of exponents equals 2 - rate changes throughout rxn as concentration changes - unit of k must be 1/MS

Chem 112 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions