Chemistry Test #2 Flashcards

1
Q

Buffered solution

A
  • Resists change in pH
  • Weak acids or bases with a common ion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the domain of Kinetics?

A

The reaction pathway, getting over the hill. Rate of reaction depends on the pathway from reactants to products. How fast the reaction is.

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

What does thermodynamics tell us?

A

Whether a reaction is spontaneous based only on the properties of reactants and products. How stable a reaction is.

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

What do thermodynamics allow us to predict?

A

The direction which a process will occur.

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

What is the common ion effect?

A

Same ions - eq shift bc of addition of ions already present in solution

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

What is the common ion effect an application of?

A

Le Chatelier’s Principle

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

What kind of solution makes up a buffer solution?

A

Weak acids + strong base
Strong acid + weak base

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

What are you adding when you add base

A

OH-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are you adding when you add acid

A

H+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When does [HA] = [A-]

A

Half equivalence point
pH=pKa

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

What is the equivalence point for a strong acid and strong base?

A

pH = 7

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

What is q

A

Heat: transfer of energy between two objects due to a temperature difference.

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

What is w

A

Work: defined as a force acting over a distance.

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

Why can you only add small quantities to a buffered solution?

A

Large qualities overload one side and there is no longer equilibrium.

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

What happens when you add OH-

A

absorbs H+, less reactant causes a shift of equilibrium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does a lower pKa mean?

A

Lower pH, more acidic, stronger acid, higher H+

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

What happens if you increase the concentration of a aqueous solution that has a common ion with the reactant?

A

Solubility decreases.

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

What is the equation for Gibbs free energy?

A

∆G = ∆H - T∆S
∆H = Change in enthalpy
T = Temperature
∆S = Change in entropy (Disorder)
∆G = Gibbs Free energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the equation for internal energy?

A

∆E = q + w

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

What does is mean if q is negative?

A

Exothermic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does it mean if q is positive?

A

Endothermic

22
Q

What does it mean is w is positive?

A

Surrounding does work on the system

23
Q

What does is mean if w is negative?

A

System does work on the surroundings

24
Q

What is the equation for work?

A

P x A x ∆h = P∆V
P = Pressure
A = Area
∆h = distance moved

25
Q

What is the difference btw unsaturated and a saturated solution?

A

Saturated solutions cannot dissolve anything because of the solute can no longer dissolve. Unsaturated solutions can still dissolve the solute.

26
Q

What is a ligand?

A

A lewis base: Electron pair donor

27
Q

What is are complex ions?

A

Metal + non metal

28
Q

What is quantitative analysis?

A

Analysis of a situation or event, especially a financial market, employing complex mathematical and statistical modeling.

29
Q

When does precipitation occur with Q and Ksp?

A

Q > Ksp until the concentration is reduced to satisfy Ksp

30
Q

When does precipitation not occur?

A

When Q < Ksp

31
Q

What is the first law of thermodynamics and its implactions?

A

Energy cannot be created or destroyed

32
Q

What is the second law of thermodynamics and its implications?

A

Any spontaneous process always causes an increase in entropy in the universe. The total energy is always constant. The entropy of the universe is always increasing.
S (Universe) = ∆S (system) + ∆S (surroundings)
Systems and surroundings are opposites.

33
Q

What is enthalpy?

A

∆H = energy released or absorbed. tells if endo or exothermic.

34
Q

What is entropy?

A

Measure of molecular randomness. The driving force of a spontaneous process is an increase of entropy in the universe. ∆S

35
Q

Which way does positional entropy increase?

A

From solid to liquid to gas

36
Q

What does more energy dispersal mean?

A

More entropy

37
Q

What is the 3rd law of thermodynamics?

A

The entropy of a perfect crystal at 0 Kelvin is 0. entropy increases with temp.

38
Q

What happens to the entropy in exothermic reaction?

A

Increase in entropy

39
Q

What happens to the entropy in endothermic reaction?

A

Decrease in entropy

40
Q

Why do particles arrange themselves as solids, liquids, and gases?

A

based on the energy levels and forces acting between the particles. movement and vibration.

41
Q

How can large molecules in cells can be assembled from smaller ones without violating the law?

A

as long as other processes that force this to happen in the cell obtain a larger increase in entropy than the decrease in entropy by the creation of the larger molecule.

42
Q

When liquids become vapor what happens and why?

A

Increase in entropy because more space to fill in the universe.

43
Q

What qualifies a process to be spontaneous?

A

When ∆G is negative and when a reaction can occur without any assistance

44
Q

How to know whether positional entropy decreases or increases?

A

look at the phases of the molecules if there is a gas it will favor the side with gas. If they are all in the same phase, look at the moles of each of the molecules.

45
Q

How to know whether the reaction will occur in the forward direction by looking at a balanced equation?

A

By comparing the reaction quotient to the equilibrium constant,

46
Q

What is the relationship between the number of hydrogen ions and anions produced by strong and weak acids?

A

Strong acids contain the same number of hydrogen ions and anions as the original dissociated strong acid molecule; weak acids contain far fewer hydrogen ions and anions than the original dissociated acid molecule.

47
Q

What is the common ion effect?

A

The common ion effect is a shift in equilibrium position that results from adding an ion that is already present in the equilibrium reaction

48
Q

How is the common ion effect useful in making buffer solutions?

A

Buffered solutions are simply solutions of weak acids or bases containing a common ion; the common ion effect is used to construct buffer solutions (they consist of a weak acid and a salt with a common anion to the acid).

49
Q

Does Ksp ever change in different solutions

A

NOOOOOOO

50
Q

How does concentration impact buffer capacity

A

A bigger concentration of buffer solution means a higher buffer capacity [HA] and [A-]

51
Q

What happens if you put too much acid or base into buffer solution?

A

Kill the buffer

52
Q
A