Exam 2 Flashcards

1
Q

In a chemical equation, what is the term for the starting material?

A

Reactants

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

In a chemical equation, what is the term for the ending material?

A

Products

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

Which law tells us that chemical equations must be balanced before and after a reaction?

A

The Law of Conservation of Mass

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

one mole is equal to what?

A

6.022 * 10^23

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

In order to go from moles to moles, what is one important factor we need?

A

We need to have the molar ratio (coefficients from balanced equation)

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

To go from Moles to Atoms we use

A

Avogadros Number

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

To go from Moles to grams we use

A

Molar Mass

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

To go from Moles to Moles we use

A

Coefficients from balanced reactions

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

What is an empirical formula?

A

An empirical formula is the simplified formula of a compound

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

What is a molecular formula?

A

A molecular formula is the true formula of a compound

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

If a formula can be reduced by the same factor, is it empirical or molecular?

A

Molecular

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

How do we determine empirical formulas?

A

If we are given that percent, simply turn it into grams (no conversion) and then convert it from grams to moles. In order to get a ratio, we must divide all of the moles by the smallest mole. Now that we have all of the values, plug them as subscripts to their corresponding compound.

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

How do we determine molecular formulas?

A

To find molecular formula, first find the empirical formula. After you have it, find the molar mass of the compound, Since we are given a molar mass (in the problem), if it does not match your calculation, divide the molar mass that you were given by the molar mass you calculated. Whatever value you get tells us our formula is off by that factor.

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

What is the oxidation state of free elements?

A

0

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

In compounds, group 1 elements have an oxidation state of

A

1

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

In compounds, fluorine has an oxidation states of

A

-1

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

Group 2 metals have an oxidation state of

A

+2

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

Group 3 ions have an oxidation state of

A

+3

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

In compounds, hydrogen has an oxidation state of

A

+1

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

In compounds, oxygen has an oxidation state of

A

-2

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

How do we identify oxidation?

A

Oxidation is the loss of electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do we identify reduction

A

Reduction is the gain of electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

t/f oxidation and reduction take place simultaneously

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

If an element is oxidized, what is its agent?

A

Reducing agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

If an element is reduced, what is its agent?

A

oxidizing agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

In the ideal gas law, what are the units?

A

atm, Kelvin, Liters, moles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the constant of the ideal gas law?

A

R

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is r equal to?

A

0.0821

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is standard temperature and pressure?

A

273 K and 1 atm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

If we have one mole of any gas at STP, what is the volume?

A

22.4 Liters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Which law tells us the relationship between volume and pressure? What is the relationship?

A

Boyles law, As volume decreases, pressure increase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Which law tells us the relationship between volume and temperature? What is the relationship?

A

Charles law, As volume increases, temperature increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Which law tells us the relationship between pressure and temperature? What is the relationship?

A

Gay Lussac law, As pressure increases, temperature increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Which law tells us the relationship between moles and volume? What is the relationship

A

Avogadro’s law, As moles increase, volume increases

35
Q

What is the equation for Boyles law?

A

P1V1=P2V2

36
Q

What is the equation for Charles Law?

A

V1/T1 = V2/T2

37
Q

What is the equation for Gay Lussac’s Law?

A

P1/T1 = P2/T2

38
Q

What is the equation for Avogadro’s Law?

A

V1/n1 = V2/n2

39
Q

What is the formula for pressure?

A

P= Force/Area

40
Q

What is the standard pressure?

A

1 atm or 760 torr

41
Q

How do we go from atm to torr?

A

multiply by 760

42
Q

How do we go from torr to atm?

A

divide by 760

43
Q

What does Dalton’s Law of Partial Pressure tell us?

A

The total pressure is equal to the sum of the individual pressures

44
Q

t/f gases usually exist as individual molecules/atoms

A

false, they exist in mixtures

45
Q

What is it called when we go from a solid to a liquid?

A

melting

46
Q

What is it called when we go from a liquid to a solid?

A

freezing

47
Q

What is it called when we go from a Liquid to gas

A

Vaporization

48
Q

What is it called when we go from a gas to a liquid?

A

condensation

49
Q

What is it called when we go from a gas to a solid?

A

sublimination

50
Q

What is it called when we go from a solid to a gas?

A

deposition

51
Q

why is solid water less dense than liquid water?

A

It is less dense because when water freezes, the molecules form a crystalline structure that is held together by h bonding. Since we know water is a polar molecule, the positive of hydrogen attracts to the negative of oxygen between other h2o molecules.

52
Q

A polar molecule has a/an _______ distribution of electrons

A

unequal

53
Q

Describe solids in terms of movement, structure, shape, volume and compressibility

A

Solids only vibrate because they have a tight structure. They have a fixed volume and shape and are incompressible (except for ice)

54
Q

Describe liquids in terms of movement, structure, shape, volume and compressibility

A

Liquids have a bit more movement, fixed volume and is incompressible

55
Q

Describe gas in terms of movement, structure, shape, volume and compressibility

A

Gases have the most kinetic movement, it does not have a fixed volume or shape and it is compressible

56
Q

Are changes of state physical or chemical changes?

A

physical

57
Q

Rank the attraction forces for gas, liquids and solids

A

Solids > Liquids > Gas

58
Q

What is the difference between intermolecular forces and covalent/ionic bonds?

A

Intermolecular forces are the bonds between 2 molecules while covalent bonds are the bonds between 2 atoms in a molecule

59
Q

Which forces are weaker? Intermolecular or covalent?

A

Intermolecular forces

60
Q

What are the three main types of IMF?

A
  1. London Dispersion
  2. Dipole-Dipole
  3. Hydrogen Bonding
61
Q

Which IMF is present in all molecules?

A

London Dispersion

62
Q

Which IMF ispresent in polar molecules?

A

Dipole Dipole

63
Q

How does Hydrogen bonding become relevant?

A

This happens when Hydrogen bonds to really electronegative elements such as F, O or N

64
Q

what is the order of the IMF forces? Strongest to weakest

A

Hbond> Dipole Dipole> London Dispersion>

65
Q

What is the relationship between IMF and phase change?

A

The stronger the IMF, the higher the boiling/melting point (more energy needed)

66
Q

What is the relationship between IMF and surface tension?

A

The stronger the IMF, the higher the surface tension

67
Q

What is the relationship between IMF and vapor pressure?

A

The stronger the IMF, the lower the vapor pressure

Strong IMF produce low amounts of evaporation (molecules are attracted)

68
Q

What is vapor?

A

When a substance is present as both a gas and a liquid

69
Q

What is the difference between vaporization and evaporation?

A

In evaporation, particles can completely escape. In vaporization, we have an equilibrium where particles are equally converting back and forth between a gas and a liquid.

70
Q

What is boiling?

A

It is a type of vaporization where evaporation takes place in the whole container rather than on the surface

71
Q

When does boiling occur?

A

When vapor pressure is equal to atmospheric pressure

72
Q

What process occurs when vapor pressure is less than atmospheric pressure?

A

Evaporation

73
Q

t/f boiling can occur at any temperature

A

true, as long as the outside pressure if the same as the vapor pressure

74
Q

What is the relationship between low pressure and boiling point?

A

At low pressure, it takes more energy to reach a boiling point which also means it takes longer

75
Q

What is the relationship between high pressure and boiling point?

A

At high pressure, it takes less energy to reach a boiling point which means itis faster

76
Q

What atmospheric pressure does the normal boiling point refer to?

A

760 torr, 1 atm

77
Q

What are the diatomic molecules?

A

hydrogen, nitrogen, oxygen, fluorine, chlorine, iodine, bromine.

78
Q

What should we remember when converting grams to atoms?

A

if you want tofind atoms of a molecule, multiply by however many atoms there are. If you want to find one specific element, multiply by however many there is.

79
Q

How is oxidation determined in a compound?

A

In an equation, if a element’s oxidation number was higher, it lost electrons because the oxidation state should be positive (more protons)

80
Q

How is reduction determined?

A

Reduction is the gain of electrons so if an element’s oxidation number went from positive to negative or (lowered), it gained electrons because it has a negative charge

81
Q

How is the agent (oxidation and reducing) stated?

A

Although we are working with individual elements, the agent will be the compound in the reactant side. Lets say Hydrogen was oxidized in H2O. Hydrogen would be oxidized but H2O would be the reducing agent.

82
Q

If a polyatomic ion has a charge, what is the oxidation number?

A

Whatever the charge is.. make sure you memorized

83
Q

How do you go from Farenheit to Celsius?

A

First subtract by 32 and then multiply by 5/9.