Final Exam Flashcards

1
Q

Atomic number

A

The number of protons in an atom

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

Mass number

A

Mass of all protons + neutrons in an atom

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

What property is the energy carried by photons most directly associated with?

A

Frequency

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

Definition of a heterogeneous mixture

A

A mixture with non-uniform composition

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

Definition of a homogeneous mixture

A

A mixture with uniform composition

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

Nano

A

10^9

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

Micro

A

10^6

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

Mega

A

10^-6

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

What is an orbital node?

A

An area around the nucleus where the probability of finding an electron is greater than zero

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

What is a net ionic equation?

A

An equation including only the molecules that are actively involved in a reaction, that are changed by the reaction. Excludes spectator ions

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

What is entropy a measure of?

A

How energy is distributed in a system. Units: J/K

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

How do you find velocity if given wavelength and frequency?

A

velocity = (wavelength)(frequency)

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

How do you calculate the energy of electrons in a hydrogen atom?

A

E = -(Rydberg energy)/(n^2)

Rydberg energy is given on the sheet, n is the principle electron orbital quantum number (1 for hydrogen)

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

How do you calculate the change in energy caused by an electron transitioning across different electron shells/levels (Bohr model rings)?

A

delta E = -(Rydberg energy)(Z/n - Z/n)

This one is given on the sheet
Z = atomic number
n = principle electron orbital quantum number

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

How do you calculate the specific heat of something if given the mass and temperature change from a calorimetric experiment?

A

qA = -qB

(C)(m)(Tf - Ti) = - (C)(m)(Tf - Ti)

The left and right sides of the equation describe two different substances, the ones the heat was transferred to in the experiment. Each has a different C (specific heat capacity)

m is mass, T is temp

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

How do you calculate the work done on a system?

A

w = - (P)(delta V)

w = delta E - delta H

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

How do you calculate partial pressures for compounds in a solution?

A

Pvap = ∑ (mole fraction)(partial pressure)

Remember that mole fraction is the moles of solute over total moles in solution

18
Q

What do weaker IMFs mean for vapor pressure and boiling point?

A

Higher vapor pressure, lower boiling point

19
Q

What do stronger IMFs mean for vapor pressure and boiling point?

A

Lower vapor pressure, higher boiling point

20
Q

Which has more potential energy, the heat of fusion or the heat of vaporization?

A

Heat of vaporization

21
Q

What predicts spontenaity?

A

Delta G, NOT delta S!

22
Q

What happens to entropy when:
Temp decreases
Volume decreases

A

Entropy decreases

23
Q

What happens to entropy when:
Temp decreases
Volume remains constant

A

Entropy decreases

24
Q

What happens to entropy when:
Temp decreases
Volume increases

A

Need more info

25
Q

What happens to entropy when:
Temp remains constant
Volume decreases

A

Entropy decreases

26
Q

What happens to entropy when:
Temp remains constant
Volume remains constant

A

Entropy remains constant

27
Q

What happens to entropy when:
Temp remains constant
Volume increases

A

Entropy increases

28
Q

What happens to entropy when:
Temp increases
Volume decreases

A

Need more info

29
Q

What happens to entropy when:
Temp increases
Volume remains constant

A

Entropy increases

30
Q

What happens to entropy when:
Temp increases
Volume increases

A

Entropy increases

31
Q

When is a rxn spontaneous?

A

When delta G is negative

32
Q

When is a rxn NOT spontaneous?

A

When delta G is positive

33
Q

In exothermic rxns, what happens to delta S?

A

It’s positive

34
Q

In endothermic rxns, what happens to delta S?

A

It’s negative

35
Q

How do you calculate the heat needed to make a substance undergo a phase change, given a specific starting temp?

A

(mass of substance)(specific heat capacity)(needed delta T)
+
(moles of substance)(molar heat of phase change)

Solve for these two and add them together. The first one is the heat needed to raise the substance’s temp to the start point of the phase change. The second one is the heat needed to actually complete the phase change.

36
Q

Which phase changes increase entropy?

A

s to l, l to g, s to g

fusion, boiling, sublimation

37
Q

Which phase changes decrease entropy?

A

g to l, l to s, g to s

condensation, crystallization, deposition

38
Q

Think about the clausius-clapeyron equation. What happens to vapor pressure as temp increases?

A

Vapor pressure also increases

39
Q

Think about the clausius-clapeyron equation. What do smaller delta Hvaps do to the graph of:
x = temp, y = vapor pressure

A

Steeper exponential increase
(half parabola, cut off at midpoint 0,0)

They shift the vertical “asymptote” closer to the y-axis

40
Q

Think about the clausius-clapeyron equation. What do larger delta Hvaps do to the graph of:
x = temp, y = vapor pressure

A

Slower exponential increase
(half parabola, cut off at midpoint 0,0)

They shift the vertical “asymptote” farther away from the y-axis

41
Q

How do you calculate mass percent of a concentration/solution?

A

(mass of solute)/(mass of solution) x100

42
Q

What does it mean if you are given a substance’s solubility (for example in g/L) in the setup to a problem?

A

It means you already know the maximum possible concentration of the substance in the solution.