Liquids and Solids

Question 1

Postulates of Kinetic Molecular Theory

Answer 1

1. particles touch
2. complicated motion
3. forces involved

Question 2

Types of forces between individual units in liquid and solid phase depend on the material

Answer 2

A. ionic compounds - ionic bonds that vary in strength depending on charge of ions and size - STRONG INTERATOMIC BONDS

B. metals - metallic bonds - BETWEEN STRENGTH INTERATOMIC BONDS

C. covalent compounds - intermolecular bonds - WEAK INTERATOMIC BONDS

Question 3

Describe dispersion forces

Answer 3

exist between nonpolar molecules

Question 4

Describe dipole-dipole forces

Answer 4

forces between polar molecules

they are weak because they are not full charges and there is separation between them

Question 5

describe hydrogen bond

Answer 5

a type of dipole-dipole bond between polar molecules

strongest IM bond

has to be bonded directly to F, O, or N as they have a high en

Question 6

How do dispersion forces arise?

Answer 6

when electrons in two atoms next to each other are placed in a way that temporary dipoles form which attract each other

Question 7

melting

Answer 7

solid to liquid

Question 8

liquid to gas

Answer 8

evaporation

Question 9

solid to gas

Answer 9

sublimation

Question 10

liquid to solid

Answer 10

freezing

Question 11

gas to liquid

Answer 11

condensation

Question 12

gas to solid

Answer 12

deposition

Question 13

is melting endothermic or exothermic?

Answer 13

endothermic

Question 14

is evaporation endothermic or exothermic?

Answer 14

endothermic

Question 15

is sublimation endothermic or exothermic?

Answer 15

endothermic

Question 16

is freezing endothermic or exothermic?

Answer 16

exothermic

Question 17

is condensation endothermic or exothermic?

Answer 17

exothermic

Question 18

is deposition endothermic or exothermic?

Answer 18

exothermic

Question 19

during melting do the bonds loosen or break?

Answer 19

the bonds loosen

Question 20

during freezing do the bonds loosen or tighten?

Answer 20

tighten

Question 21

during sublimation for bonds loosen or break?

Answer 21

break

Question 22

enthlapy

Answer 22

POTENTIAL ENERGY CHANGE

Question 23

thermal energy

Answer 23

sum of all kinetic energies of particles in sample of matter

Question 24

relationship between heat of the surroundings and enthlapy change of the system

Answer 24

delta H = -q

Question 25

is delta H fusion an intensive or extensive property?

Answer 25

intensive property

Question 26

is delta H an intensive or extensive property?

Answer 26

extensive property

Question 27

equilibrium vapor pressure

Answer 27

the pressure that a vapor would exert above its liquid when in equilibrium with the liquid

Question 28

how does equilibrium vapor pressure affect strong forces?

Answer 28

less vapor particles lower vapor pressure

Question 29

how does equilibrium vapor pressure affect weak bonds?

Answer 29

more vapor particles higher vapor pressure

Question 30

surface tension

Answer 30

unbalanced forces at surface of a liquid creating a film-like quality to the surface

Question 31

viscosity

Answer 31

resistance to flow

Question 32

how is boiling point related to IM bonds?

Answer 32

high boiling point = strong IM bonds

Question 33

how is melting point related to IM bonds?

Answer 33

a high melting point = strong IM bonds

Question 34

how does viscosity relate to IM bonds?

Answer 34

high viscosity = strong IM bonds

Question 35

how does surface tension relate to IM bonds?

Answer 35

high surface tension = strong IM bonds

Question 36

how does vapor pressure relate to IM bonds?

Answer 36

high vapor pressure = weak IM bonds

Question 37

what factors affect strength of dipole-dipole bonds?

Answer 37

the polarity of the molecule

Question 38

what factors affect strength dispersion forces?

Answer 38

the number of e-s mass - the heavier the slower - the slower the more time to interact length as more than one dispersion force can exist between neighboring molecules - the longer the chain the stronger the IM bonds

Question 39

entropy

Answer 39

the disorder or uncertainty in a system

Question 40

critical point

Answer 40

absolute highest temperature and pressure that there is liquid phase

Question 41

triple point

Answer 41

ALL phases at equilibrium

Question 42

crystal

Answer 42

solid piece with flat faces and sharp angles between those faces

Question 43

crystal form

Answer 43

arrangement of ions on atomic level which results from regular geometric arrangement of particles in the crystal lattice

Question 44

unit cell

Answer 44

a small set of particles forms the building block of the solid crystal

Question 45

crystal structure

Answer 45

the shape of the unit cell

Question 46

how to determine if polar?

Answer 46

asymmetrical and charged