Chem 2 Exam 1 Ch 11 And 12

Front 1

phase

Back 1

Any part of a system that looks uniform throughout

Front 2

phase change

Back 2

a change from one physica state to another (liquid, solid, gas)

Front 3

heat of fusion

Back 3

the heat needed to melt 1mol of a pure substance

Front 4

heat of vaporization

Back 4

heat needed to boil 1mol of a pure substance

Front 5

phase diagram

Back 5

graph that summarizes conditions which different states of a substance are stable

Hint 5

liquid is more dense then curve leans left &melting point decrease with pressure
less dense,leans right and increases with pressure

Front 6

london dispersion force

Back 6

occurs in all atoms
weak attractive forces
increases with molar mass

Front 7

dipole-dipole

Back 7

weak attractive forces between molecules with DIPOLE MOMENTS
must have polar covalent bonds and asymmetric

Front 8

vapor pressure

Back 8

partial pressure of the vapor over a liquid
temp increases, vp increases
intermolecular forces increase, vp decreases

Front 9

boiling point

Back 9

temp at which vp of a liquid is equal to the pressure exerted on liquid
normal bp is 1 atm

Front 10

surface tension

Back 10

energy required to increase the surface area of a liquid by a unit amount
intermolecular forces increase, surface tension increases

Front 11

viscosity

Back 11

the resistance to flow exhibited by all liquids and gases
intermolecular forces increase, viscosity increases

Front 12

hydrogen bonds

Back 12

a force that exists between a hydrogen atom covalently bonded to a very electronegative atom (N,O,F)

Front 13

solid

Back 13

nearly incompressible state of matter with a well defined shape

Front 14

molecular solid

Back 14

atoms or molecules
intermolecular forces
low melting point
soft and brittle
non conductive
ex: Ne, H2O, CO2

Front 15

polymeric solid

Back 15

very large molecules
intermolecular forces
low melting point
soft to hard
non conductive
ex:rubber, plastics, proteins

Front 16

ionic solids

Back 16

ions
ionic bonding
low to very high melting point
hard and brittle
non conductive, except as liquids
ex: NaCl, K2SO4

Front 17

metallic solids

Back 17

metal atoms
metallic bonding
variable melting point
various hardness, malleable
conductive
ex: Fe, Cu, Ag

Front 18

network solids

Back 18

atoms
covalent bonding
very high melting point
very hard
usually non conductive
ex: diamond, graphite

Front 19

crystalline solid

Back 19

composed of one or more crystals
well defined ordered structure in 3D

Front 20

amorphous solid

Back 20

disordered structure

Front 21

how many atoms are in a simple cubic cell

Back 21

1atom

Front 22

how many atoms are in a body centered cubic cell

Back 22

2atoms

Front 23

how many atoms are in a face centered cubic cell

Back 23

4atoms

Front 24

coordinating number

Back 24

number of nearest neigboring atoms to an atom

Front 25

solution

Back 25

a homogeneous mixture of two or more substances

Front 26

solute

Back 26

dissolved in substance
lesser amount

Front 27

solvent

Back 27

dissolving medium
greater amount

Front 28

solubility

Back 28

amount of a substance that will dissolve in a solvent

Front 29

saturated solution

Back 29

solution holding as much solute as is allowed at a stated temperature

Front 30

supersaturated solution

Back 30

a solution that contains more solute than is allowed at a given temperature. unstable solutions

Front 31

like dissolves like

Back 31

the more similar 2 compounds are the more likely one is soluble in the other (polar or non polar)

Front 32

miscible fluids

Back 32

fluids that dissolve each other in all proportions
these are solutions

Front 33

immiscible fluids

Back 33

2 fluids that do not mix
these are not solutions

Front 34

henry's law

Back 34

S=(kH)(P)

S is solubility of the gas
kH is henry's law constant characteristic of the solution
P is partial pressure of the gas

Front 35

percent composition

Back 35

amount of solute / amount of solution × 100%
w/w = g/g v/v = mL/mL w/v =g/mL

Front 36

molarity (M)

Back 36

moles of solute / liter of solution

Front 37

molality (m)

Back 37

moles of solute / kg solvent

Front 38

mole fraction

Back 38

X = moles of solute (solvent) / moles solute + moles solvent

Front 39

diluton equation

Back 39

c1v1 = c2v2

concentration and volume of a solution are inversely proportional

Front 40

vapor pressure of solution

Back 40

uses mole fractions
change in Psolvent = (Ppuresolvent)(Xsolute)
Psoln = Ppuresolvent - change in Psolvent

Front 41

Raoult's law

Back 41

vapor pressure total = PsolventXsolvent + PsoluteXsolute

Front 42

freezing point depression

Back 42

find ◇Tf (◇Tf = Kf × cm)
Tf = Tof - ◇Tf

uses molality

Front 43

boiling point elevation

Back 43

find ◇Tb (◇Tb= Kb × cm)
Tb = Tob - ◇Tb

uses molality

Front 44

colligative properties

Back 44

properties that depend on solute concentration in a solution but not on the chemical identity of the solute

Front 45

semipermeable membrane

Back 45

certain membranes allow passage of solvent molecules but not solute particles

Front 46

osmosis

Back 46

phenomenon of solvent flow through a semipermeable membrane to equalize solute concentrations on both sides of the membrane

Front 47

osmotic pressure (pi)

Back 47

equal to the pressure that, when applied to the solution, just stops osmosis

pi as a variable

pi = (i)(CM)(R)(T)

R= ideal gas constant .0831
T=temp in K
CM= molarity
i= number of particles

Front 48

osmolarity (osmol)

Back 48

osmolarity = i × CM

Front 49

colloid

Back 49

a solution in which the solute diameter is between 1nm and 1000nm
very large surface areas
scatter light
form stable dispersions

Front 50

tyndall effect

Back 50

phenomenon in which light passing thru a colloid is scattered by colloid sized particles

Front 51

sol

Back 51

consists of solid particles dispersed in liquid
ex: jelly

Front 52

aerosol

Back 52

consists of liquid droplets OR solid particles dispersed in gas
ex: clouds, smoke

Front 53

emulsion

Back 53

consists of liquid droplets dispersed in another liquid
ex: milk, mayo

Front 54

foam

Back 54

consists of gas dispersed in a solid or liquid
ex: whipped cream, marshmallows

Front 55

gel

Back 55

consists of liquid dispersed throughout a solid
ex: cheese, butter

Front 56

melting

Back 56

solid to liquid

Front 57

freezing

Back 57

liquid to solid

Front 58

vaporization

Back 58

liquid to gas

Front 59

condensation

Back 59

gas to liquid

Front 60

sublimation

Back 60

solid to gas

Front 61

deposition

Back 61

gas to solid