Chem 112 First Test

Front 1

List the 5 organic compounds and the number of carbons they each have.

Back 1

Methane- 1 Carbon
Ethane- 2 Carbons
Propane- 3
Butane- 4
Pentane- 5

Front 2

If two substances have the same molecular formula, but different shapes, they are called __________.

Back 2

Isomers

Front 3

Why will the ideal gas law never equal zero?

Back 3

PV can never equal zero because volume can never be zero.

Front 4

What shape is a graph comparing number of molecules of a gas and the average temperature of the molecules?

Back 4

Normal bell shaped.

Front 5

A gas is in constant _______, occupies the _________ space and has widely __________ molecules.

Back 5

motion,
entire,
seperated

Front 6

A liquid is in constant ________, and the temperature of the molecules is directly proportional to their _________ energy.

Back 6

motion,
kinetic

Front 7

Intermolecular forces are:

Back 7

the bonds between molecules that hold the molecules together.

Front 8

True or False:
Intermolecular forces are stronger then the average covalent bond.

Back 8

False

Front 9

True or False:
The higher a substances boiling point, the better liquid it makes.

Back 9

True

Front 10

Intermolecular forces get stronger as the boiling point __________ (increases or decreases)

Back 10

Increases

Front 11

True or False:
Dispersion forces only apply to large molecules.

Back 11

False, dispersion forces apply to all molecules.

Front 12

Dispersion forces are defined as the...

Back 12

Instantaneous polorization of molecules resulting in attraction.

Front 13

Dipole-Dipole interactions apply only to polar molecules. Explain.

Back 13

If a molecule is nonpolar it has no charge and can therefore not attract any other molecule.

Front 14

True or False:
All substances with hydrogen bonding also have dipole interactions.

Back 14

False I think.

Front 15

List the three requirements of hydrogen bonding:

Back 15

1. Must have H covalently linked to X.
2. X must be F, O or N.
3. The X atom must have at least one lone pair.

Front 16

Why are F, O and N the only three atoms (besides H) that are involved in hydrogen bonding?

Back 16

F, O and N are very electronegative atoms and only they have the power to steal away hydrogen's electron.

Front 17

Why is hydrogen so special when it comes to hydrogen bonding? Why can't all elements bond in this way?

Back 17

Hydrogen is the only element that bonds within the 1s shell, so when it's electron is pulled away, it's nucleus is exposed directly.

Front 18

What is hydrogen attracted to on the F, O or N atom?

Back 18

The lone pair(s).

Front 19

Evaporation is AKA _______.

Back 19

Vaporization

Front 20

When the number of water molecules leaving the liquid state and returning from the gaseous state is equal, this system is said to be in:

Back 20

Dynamic equilibrium

Front 21

The number of water molecules that are leaving the liquid state for the gaseous state is called the:

Back 21

Vapor pressure

Front 22

When the temperature of a liquid increases, so does it's ________ __________.

Back 22

Vapor pressure

Front 23

Boiling point

Back 23

The temp at which the vapor pressure reached the pressure above the liquid.

Front 24

Normal Boiling Point

Back 24

The temp at which the vapor pressure of a liquid reaches 1.00 atm.

Front 25

The surface of a liquid is different from the rest of the liquid. This is called a:

Back 25

Surface film

Front 26

Surface film is measured by:

Back 26

Surface tension

Front 27

Describe surface tension.

Back 27

The molecules on the surface of the liquid are more compact.

Front 28

Intermolecular forces are also known as:

Back 28

Cohesive forces

Front 29

When a liquid interacts with the side of a container, these forces are called:

Back 29

Adhesive forces

Front 30

Describe capillary attraction.

Back 30

When water travels up a tube places in a bigger recepticle of water.

Front 31

True or False:
The kinetic energy of molecules in a solid are not directly proportional to the temperature.

Back 31

False, they are proportional.

Front 32

List the four types of solids:

Back 32

1. Ionic
2. Molecular
3. Network
4. Metallic

Front 33

Network solids don't melt well because they're...

Back 33

connected together with covalent bonds.

Front 34

Ionic solids have a ______ meelting point, while molecular solids have a _____ melting point.

Back 34

high, low

Front 35

When a network solid is pulled apart and the bonds are broken the solid appears to melt, but it is really a __________ reaction.

Back 35

Decomposition

Front 36

Define boiling point.

Back 36

Temp at which liquid and gas states are in equilibrium.

Front 37

Define melting point:

Back 37

Temp at which solid and liquid states are at equilibrium.

Front 38

Define sublimation:

Back 38

When something goes directly from a solid to a gas.

Front 39

Define deposition:

Back 39

When a gas goes directly to a solid.

Front 40

Define triple point:

Back 40

All 3 states of matter can exist at the same time in equilibrium.

Front 41

Define critical point:

Back 41

The point at which you can't force a gas into a liquid, regardless of pressure forces.

Front 42

Define supercritical fluid:

Back 42

Past the critical point. Not a gas or a liquid, behaves as a fluid.

Front 43

A phase diagram is used to:

Back 43

figure out what phase a substance exists in.

Front 44

The amount of heat required to change a solid to a liquid is called the:

Back 44

Molar heat of fusion (Delta H fus)

Front 45

The amoutn of heat requires to change a liquid to a gas is called the:

Back 45

Molar heat of vaporization (delta H vap)

Front 46

Define intramolecular forces:

Back 46

When a long, dangly molecule wraps around and interacts with it's own tail.

Front 47

If heat is released in a system, then the value of deltaHfus or deltaHvap will be ___________.

Back 47

Negative

Front 48

Define heat capacity:

Back 48

Amount of heat required to change the temp of a sample 1.00 degree C.

Front 49

Define Specific Heat Capacity:

Back 49

Amount of heat required to change the temp of 1.00g of a sample 1.00 degree C.

Front 50

Heat capacity is quantity _________ while specific heat capacity is quantity ____________.

Back 50

independant, dependant

Front 51

If the specific heat of ice is 2.09 J/gC, for every gram of the substance you have, you must add _________ J.

Back 51

2.09

Front 52

If a system is endothermic, will the total heat change be positive or negative?

Back 52

Positive

Front 53

How many kJ is 980 J?

Back 53

.98 kJ

Front 54

The solute is the substance...

Back 54

being dissolved

Front 55

The solvent is the substance...

Back 55

doing the dissolving

Front 56

Compare and contrast Molarity with Molality and include why molarity can often be less then accurate.

Back 56

Molarity deals with volume which is difficult to read accuratly. Molality deals with weight.

Front 57

Define Mole Fraction

Back 57

Moles of one component per total moles present.

Front 58

True or False
The total of all the mole fractions for a given substance will add up to 100.

Back 58

False, they add up to 1.

Front 59

What is the formula for molality?

Back 59

m = moles/kg

Front 60

How many kg is 1256g?

Back 60

1.26 kg