unit 2

Question 1

assume you have a substance that plots right on the liquid-vapor equilibrium line on its phase diagram. if you raise the temperature slightly and keep the same pressure, the substance will now be

Answer 1

a gas

Question 2

the point on a phase diagram that indicates the temperature and pressure conditions at which the solid, liquid, and vapor of the substance can coexist at equilibrium is known as the

Answer 2

triple point

Question 3

what happens to the INTERmoleular forces between particles in a substance as it changes from a liquid to a gas?

Answer 3

the intermolecular forces WEAKEN

Question 4

the process of changing from solid to gas is known as

Answer 4

sublimation

Question 5

equilibrium is characterized by

Answer 5

opposing processes occurring at equal rates

Question 6

diffusion is much slower in liquids than in gases because

Answer 6

liquid particles are closer together

Question 7

liquids are more ordered than gases because liquids have

Answer 7

stronger intermolecular forces and lower mobility of the particles.

Question 8

if energy as heat is removed, most liquids will eventually

Answer 8

freeze

Question 9

according to the kinetic-molecular theory, particles in a liquid

Answer 9

move around randomly and constantly

Question 10

a liquid becomes a gas during

Answer 10

evaporation

Question 11

roles water plays in biological systems:

Answer 11

> transport materials into and out of cells or throughout the body of plants

> dissolves many substances, especially polar (sugar) and ionic (salt) substances; electrocytes

> participates in biochemical reactions (photosynthesis)

Question 12

if water molecules were not linked by hydrogen bonds to form groups in liquid water, what would be the physical state of water at room temperature?

Answer 12

gas

Question 13

water’s relatively high boiling point is the result of

Answer 13

hydrogen bonding

Question 14

the bond between oxygen and hydrogen in a water molecule is

Answer 14

polar-covalent

Question 15

what is the reason for the relatively low density of ice?

Answer 15

empty space between molecules.

Question 16

which is an example of an amorphous solid?

Answer 16

glass

Question 17

which of the following is a physical property of crystalline solids?

Answer 17

definite shape

Question 18

the three states of matter of a particular substance, in order of strength of intermolecular forces from LEAST -> GREATEST

Answer 18

gas, liquid, solid

Question 19

according to the kinetic-molecular theory, particles in solids

Answer 19

have the least amount of kinetic energy

Question 20

amorphous solids have no definite melting point because

Answer 20

their particles are arranged randomly.

Question 21

which of the following is an assumption of the kinetic-molecular theory of gases?

Answer 21

the temperature of a gas depends on the average kinetic energy of the gas particles.

Question 22

which states of matter are fluid?

Answer 22

gases and liquids

Question 23

if a gas had the same temperature throughout, which gas molecule has the HIGHEST average velocity?

Answer 23

H2

Question 24

which of the following is NOT a physical property of gases?

Answer 24

high density

Question 25

rate of effusion and diffusion of different gases are proportional to their

Answer 25

particle velocities

Question 26

which of the following changes is a chemical change of matter?

Answer 26

vinegar combining with baking soda to produce carbon dioxide

Question 27

which statement best describes an element?

Answer 27

a pure substance made up of only one kind of atom

Question 28

what is the difference between a mixture and a compound?

Answer 28

mixtures can be separated by physical processes

Question 29

which state of matter is composed of atoms that have lost many of their electrons

Answer 29

plasma

Question 30

a change in a substance that does NOT involve a change in the identity of the substance is called a(n)