Liquids and Solids Exam 1 Flashcards Preview

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Flashcards in Liquids and Solids Exam 1 Deck (32)
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1

Surface tension

(greek letter looking like y); resistance for the surface of the liquid to an external force because of the attractive forces between molecules. Decreases with increasing T (higher T = higher KE); decreases with lower attractive forces

2

Cohesive forces

forces between like molecules (ex: droplets on waxed car(stays on top as a bead))

3

Adhesive forces

forces between unlike molecules (droplet spreads out over surface)

4

capillary action

ex of adhesive force; used in blood tests and in paper chromatography to draw liquid up a tube.

5

viscosity

resistance to flow of a liquid and is a result of cohesive forces. As T increases, Viscosity decreases (higher KE)

6

Vapor Pressure

partial pressure of a gas located directly above a liquid.

Energy of evaporation is measured as delta Hvap, enthalpy of vaporization. No T change in this process; it is endothermic (heat enters system)

7

Boiling point

When the temperature increases along with the vapor pressure, and the vapor pressure equals the atmospheric pressure, the liquid will begin to boil.

8

Critical point

when the density of the liquid equals that of the gas and the surface tension equals 0, then the substance has reached its critical temperature and critical pressure.

9

network covalent solids

solid composed of covalent bonds. ex: graphite, diamond, nanotubes; mostly nonconductors

10

metallic

(cations, delocalized e-); range of mp; malleable; insoluble; ductile; good conductors

11

ionic

(cations, anions);(electrostatics); regularity; high mp; at least slightly soluble; aqueous conductor; solid nonconductor; hard

12

nonpolar molecular

(atoms or nonpolar molecules); (dispersion forces); soft, low mp, some sublime, some are soluble

13

polar molecular

dipole-dipole; low mp; some are soluble

14

h-bonded molecular

(h-bonds); low mp; some are soluble

15

Delta H fusion

enthalpy of melting

16

sublimation

solid to gas

17

deposition

gas to solid

18

solid to liquid

melting (+) (endothermic)

19

liquid to solid

freezing (-) (exothermic)

20

vaporization

liquid to gas (+) (endothermic)

21

condensation

gas to liquid (-) (exothermic)

22

supercooled liquid

a cooled liquid that has no place for crystals to form

23

superheated liquid

a heated liquid that has no place for bubbles to form

24

isobar

line at constant pressure

25

isotherm

line at constant temperature

26

intermolecular forces

when two molecules come into proximity of each other, they exert intermolecular forces of each other. (ex: h-bonding, dipole-dipole, london dispersion)

27

intramolecular forces

forces within bonds (ex: ionic, covalent, metallic)

28

Van der Waal

forces that are both london and dipole

29

instantaneous dipoles

temporary dipole created in the molecule with a partially negative and partially positive charge. the dipole is drawn (e- go to one side)

30

polarizability

ability for an atom or molecule to form instantaneous dipoles, and it increases as volume occupied by electrons (i.e. size) increases.