test 11

Question 1

name the 3 types of intermolecular forces

Answer 1

1. dipole-dipole force
2. hydrogen bonds
3. dispersion forces

Question 2

an intermolecular force; the attraction of the positive end of one polar molecule to the negative end of another polar molecule

Answer 2

dipole-dipole force

Question 3

a special dipole-dipole force involving hydrogen and a highly electronegative element

Answer 3

hydrogen bonds

Question 4

when bonded with hydrogen which highly electronegative elements cause the shared electrons to shift away from the hydrogen atoms, because of their greater electronegativity?

Answer 4

fluorine, oxygen, or nitrogen.

Question 5

which intermolecular force is the strongest and why?

Answer 5

hydrogen bonds. the combination of a high polarity and proximity produces the strongest

Question 6

a substance is typically about________ denser as a solid than as a liquid and what is the exception?

Answer 6

10% and water

Question 7

completely describe what happens as water’s temperature drops.

Answer 7

down to a temperature of 4*C, water becomes increasingly dense, but as it cools below this temperature, hydrogen bonds and dipole-dipole forces cause water molecules to spread apart from each other, assembling into an open hexagonal lattice. increased space between the molecules causes ice to be less dense than water, which makes it float

Question 8

ionic and metallic solids are usually___________

Answer 8

crystalline

Question 9

give 5 examples of amorphous solids

Answer 9

1. rubber
2. some plastics
3. asphalt
4. paraffin
5. amorphous sulfur

Question 10

the temperature at which a substance changes between the solid and liquid states is called what?

Answer 10

melting point

Question 11

what is the transformation from a solid to a liquid?

Answer 11

melting

Question 12

crystalline substance have _________melting points

Answer 12

distinct

Question 13

the direct change in state from the solid to the gaseous state

Answer 13

sublimation

Question 14

what are the 7 basic crystals

Answer 14

1. cubic
2. tetreagonal
3. rhombohedral
4. triclinic
5. monoclinic
6. hexagonal
7. orthorhombic

Question 15

elements or compounds that can form more than one type of crystal lattice are called what

Answer 15

polymorphous

Question 16

the ———– of a crystal is the energy released when gaseous particles form crystals

Answer 16

lattice energy

Question 17

the magnitude of the electrical charges in a crystal affects its ——

Answer 17

stability

Question 18

why does particle size affect binding forces

Answer 18

small particles can be more tightly bound than large particles

Question 19

the ———– of a crystal also affects the binding forces

Answer 19

geometric structure

Question 20

what affects the strength of a crystal

Answer 20

size of particles
geometric structure
the charges of the particles

Question 21

a substance that is added to a liquid that acts to reduce the surface tension of that liquid by interfering with hydrogen bonds

Answer 21

surfactants

Question 22

a liquid’s ability to resist flowing

Answer 22

viscosity

Question 23

the reverse of vaporization- it is the formation of a liquid from its gaseous state

Answer 23

condensation

Question 24

evaporation is a ——— process

Answer 24

cooling

Question 25

what type of attractions allow quick evaporation

Answer 25

weak

Question 26

when the two processes of condensation and evaporation balance each other so that no net effect can be observed

Answer 26

dynamic equilibrium

Question 27

the temperature at which the vapor pressure equals the applied pressure

Answer 27

boiling point

Question 28

what can condense and even solidify any gas

Answer 28

low temperatures and high pressures

Question 29

the highest temperature at which a gas can be liquified

Answer 29

critical temperature (Tc)

Question 30

when would most evaporation occur

Answer 30

high temps

Question 31

what affects evaporation

Answer 31

temperature and molecular attraction

Question 32

a solid in which the particles occur in random positions with no orderly pattern. Examples include asphalt and paraffin

Answer 32

amorphous solid

Question 33

a state of matter in which the particles have relatively little energy, cannot overcome the attractive forces, and remain in fixed positions with set distances between them. It has fixed a volume and is relatively incompressible

Answer 33

solid

Question 34

the basic building block for any type of crystal; the section of a crystal lattice that contains one formula unit of the compound or one repeating segment of the overall lattice strucure

Answer 34

unit cell

Question 35

one of two or more forms of a polymorphous element that exists in the same physical state

Answer 35

allotropes

Question 36

the curved upper surface of a column of liquid that results from intermolecular attractions within the liquid and between the liquid and its container

Answer 36

meniscus

Question 37

the movement of a liquid up a narrow tube caused by adhesion between molecules in the walls of the tube and the molecules of the liquid

Answer 37

capillary action

Question 38

a general term for a physical change from the liquid state to the vapor or gaseous state

Answer 38

vaporization

Question 39

a physical change from the liquid state to the gaseous state that occurs at the surface of a liquid when the temperature is between the substance’s freezing and boiling points

Answer 39

evaporation

Question 40

when pressure is exerted by a vapor in equilibrium its solid or liquid state at a specified temperature

Answer 40

vapor pressure

Question 41

a technique used to separate a mixture by evaporating its components at their boiling points and then condensing and collecting the vapors

Answer 41

distillation

Question 42

3 types of vaporization

Answer 42

evaporation
boiling
condensation