Chemistry - Phase And Phase Changes

Front 1

What are liquids and solids often referred to as?

Back 1

The condensed phases

Front 2

How are atoms or molecules held in liquid?

Back 2

They are held close together with little space between them

Front 3

What does this result in?

Back 3

It makes liquids have definite volumes that cannot easily be expanded or compressed

Front 4

Can liquid diffuse and evaporate?

Back 4

Yes

Front 5

What do liquids form when they mix, both with each other and with other phases?

Back 5

They form solutions

Front 6

What is the degree to which two liquids can mix?

Back 6

It is called their miscibility

Front 7

What are oil and water?

Back 7

They are almost completely immiscible

Front 8

What can two immiscible liquids form?

Back 8

A fairly homogenous mixture called an emulsion

Front 9

What may a solid be?

Back 9

It may be crystalline or amorphous

Front 10

What is the structure of a crystalline solid?

Back 10

It possess an ordered structure

Front 11

How do is atoms exist?

Back 11

They exist in a specific three-dimensional geometric arrangement with repeating patterns of atoms, ions, or molecules

Front 12

What is the structure of an amorphous solid?

Back 12

It has no ordered three-dimensional arrangement, although the molecules are also fixed in place

Front 13

What are most solids?

Back 13

Most are crystalline in structure

Front 14

What are ionic solids?

Back 14

They are aggregates of positively and negatively charged ions

Front 15

Are there any discrete molecules?

Back 15

No

Front 16

What are the physical properties of ionic solids?

Back 16

They include high melting points, high boiling points, and poor electrical conductivity in the solid phase

Front 17

What are these properties due to?

Back 17

They are due to the compounds’ strong electrostatic interactions, which also cause the ions to be relatively immobile

Front 18

What are metallic solids?

Back 18

They consist of metal atoms packed together as closely as possible

Front 19

What are characteristics of metallic solids?

Back 19

They have high melting and boiling points as a result of their strong covalent attractions

Front 20

What are pure metallic structures?

Back 20

They are usually described as layers of spheres of roughly similar radii

Front 21

What are repeating units of crystals?

Back 21

They are represented by unit cells

Front 22

What are the types of unit cells?

Back 22

Simple cubic, body-centered cubic, and face-centered cubic

Front 23

What are atoms represented by?

Back 23

They are represented by points

Front 24

In an isolated system, are phase changes reversible?

Back 24

Yes

Front 25

Does an equilibrium exist between phases?

Back 25

Yes

Front 26

What is the temperature of a liquid related to?

Back 26

It is related to the average kinetic energy of the liquid molecules

Front 27

What is evaporation or vaporization

Back 27

It is when some molecules near the surface of a liquid have enough energy to leave the liquid phase and escape into the gaseous phase

Front 28

What happens each time the liquid loses a high-energy particle?

Back 28

The temperature of the remaining liquid decreases

Front 29

What does this imply about evaporation?

Back 29

It is a cooling process

Front 30

What is condensation?

Back 30

It is when some gas molecules go back into the liquid phase

Front 31

What is vapor pressure?

Back 31

It is the pressure that the gas exerts over the liquid

Front 32

How does vapor pressure relate to temperature?

Back 32

It increases with temperatures

Front 33

Why?

Back 33

Because more molecules have sufficient kinetic energy to escape into the gas phase

Front 34

What is the term for the temperature at which the vapor pressure of the liquid equals the external pressure?

Back 34

The boiling point

Front 35

What is the transition from solid to liquid?

Back 35

It is called fusion or melting

Front 36

What is the process from liquid to solid?

Back 36

It is called solidification, crystallization, or freezing

Front 37

What is it called when a solid goes directly into the gas phase?

Back 37

It is called sublimation

Front 38

What is gaseous to the solid phase?

Back 38

It is called deposition

Front 39

What does a phase diagram depict?

Back 39

It shows the phases and phase equilibria of a substance at defined temperatures and pressures

Front 40

Where is the gas typically found?

Back 40

It is typically found at high temperature and low pressure

Front 41

Where is the solid phase found?

Back 41

Low temperature and high pressure

Front 42

Where is the liquid phase found?

Back 42

It is found at high temperature and high pressure

Front 43

What is the triple point?

Back 43

It is the point on a phase diagram where the three lines meet

Front 44

What is the critical point?

Back 44

It is the temperature and pressure above which no distinction between liquid and gas is possible

Front 45

What does Raoult’s Law do?

Back 45

It enables one to determine the relationship between the vapor pressure of A and the concentration of liquid A in the solution

Front 46

What are colligative properties?

Back 46

They are physical properties derived solely from the number of particles present, not the nature of those particles

Front 47

What is the formula for calculating freezing-point depression?

Back 47

Tf = Kfm. Tf is the freezing-point depression, Kf is a proportionality constant, and m is the molality of the solution

Front 48

When does a liquid boil?

Back 48

It boils when its vapor pressure equals the atmospheric pressure

Front 49

What if the vapor pressure of a solution is lower than that of the pure solvent?

Back 49

More energy and a higher temperature will be required before its vapor pressure equals atmospheric pressure