liquids and solids condensed states of matter solids, liquids

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Liquids and Solids Condensed States of Matter Solids, Liquids

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Page 1: Liquids and Solids Condensed States of Matter Solids, Liquids

Liquids and Solids

Condensed States of Matter

Solids, Liquids

Page 2: Liquids and Solids Condensed States of Matter Solids, Liquids

What is the differencebetween a gas and liquids/solids?•Something to do with density•And volume•And taking the shape of its container•Why?

Page 3: Liquids and Solids Condensed States of Matter Solids, Liquids

Why Aren’t All Substances Gases?•Democritus’ theory of atoms was dismissed

because why don’t all these particles fall apart like sand?

• If there is nothing holding molecules together, then they should be free to go where ever. Just like an ideal gas.

Page 4: Liquids and Solids Condensed States of Matter Solids, Liquids

Physical Properties

Gas Liquid SolidsHighly Compressible Slightly Slightly

Low Density High Density High Density

Fills Container Definite volume Rigid volume

Assumes Shape Assumes shape Retains own

Rapid diffusion Slow diffusion Extremely Slow,surface

High expansion onheating

Low expansion onheating

Low expansion onheating

Page 5: Liquids and Solids Condensed States of Matter Solids, Liquids

Condensed States

•Liquids and Solids•Higher densities than gas Due to lower temperature and attractions

Page 6: Liquids and Solids Condensed States of Matter Solids, Liquids

Physical Properties• Gas

▫total disorder▫ freedom of motion▫particles far apart • Solid

▫ordered arrangement▫particles can vibrate▫ remain fixed position▫particles close together•Liquid

•Disorder•free to move relative to each other•particles close

Page 7: Liquids and Solids Condensed States of Matter Solids, Liquids

Kinetic-Molecular Theory•The state of a substance depends on the

strength of the attraction between its particles

•And the average kinetic energy (temperature)

•Remember ideal gases do not attract!•Solids and liquids do. •So do “real” gases.

Page 8: Liquids and Solids Condensed States of Matter Solids, Liquids

Intramolecular Forces

•Attractions within a molecule – covalent bonds▫Share electrons between nucleii▫Stored energy

Page 9: Liquids and Solids Condensed States of Matter Solids, Liquids

Intermolecular ForcesForces between molecules•Dipole-Dipole in polar molecules

▫Strong forces▫Hydrogen Bond are special Dipole-dipole

• Dispersion in non polar▫Explains why non-polar molecules can be

liquids and solids•Van der Waal in long chains

▫Longer chains interact▫Polymers are very long chains, solids

Page 10: Liquids and Solids Condensed States of Matter Solids, Liquids

Dipole Dipole Interactions•Dipoles

▫partial negative and partial positive charge

•Partial negative and positive attract▫Dipole - Dipole Forces▫Hydrogen bond - Strongest dipole-dipole

+ - + -

Page 11: Liquids and Solids Condensed States of Matter Solids, Liquids

Water

•Water is a polar molecule• It has a positive end and a negative end•Oxygen is negative•Hydrogen is positive•Any time you have oxygen to hydrogen

bond▫Get hydrogen bonding

Page 12: Liquids and Solids Condensed States of Matter Solids, Liquids

Hydrogen Bonding

O

HH

-

+

+

O

HH

-

Strong interaction

Page 13: Liquids and Solids Condensed States of Matter Solids, Liquids

O

HH

O

H

HO

HH

O

HH

O

H

H

Intermolecular bonds are responsible for the “condensed states

Page 14: Liquids and Solids Condensed States of Matter Solids, Liquids

Dispersion Forces

• Induced Dipole▫electron clouds are deformed

•Makes gases “real”

+ -+ -

Page 15: Liquids and Solids Condensed States of Matter Solids, Liquids
Page 16: Liquids and Solids Condensed States of Matter Solids, Liquids

Induced Dipoles

• When non-polar molecules approach ▫ They negative electron

clouds repel▫ Inducing a dipole▫ Which allows the

molecules to interact

• Helium freezes at 3K▫ Have to move really

slowly to induce a dipole

-300

-250

-200

-150

-100

-50

0

helium

neonargon

krypton

xenon

Freezing Point

Page 17: Liquids and Solids Condensed States of Matter Solids, Liquids

van der Waals Forces

Alkane Boiling Points

-170

-70-45

5

35

65

95

125

-200

-150

-100

-50

0

50

100

150

methaneethane

propanebutane

pentane

hexane

heptaneoctane

•The longer the chain, the higher the boiling point

•The chains get tangled like spaghetti

•Takes more energy to break intermolecular tangles

•It has a higher boiling point

Page 18: Liquids and Solids Condensed States of Matter Solids, Liquids

Boiling Points

Smaller atoms are more electronegative, so they have more polar bonds. H – bonding is more effective so they have higher boiling points

The higher the molecular weightThe higher the boiling point.Ask why!

Page 19: Liquids and Solids Condensed States of Matter Solids, Liquids

Boiling point – • the temperature at which the vapor

pressure equal the atmospheric pressure

•Higher temps = higher kinetic energy•Lower atmospheric pressure requires less

energy

Normal boiling point – the boiling point at 1 atm

Page 20: Liquids and Solids Condensed States of Matter Solids, Liquids

Rules for naming organic compounds

1. Find the longest continuous chain2. Number the longest chain to give the

groups/ branches the lowest number possible( left to right or right to left)

3. Add “yl” to prefixes for the groups4. Order groups by alphabet and write

the carbon number they are attached to(use prefixes di, tri, if needed)

Page 21: Liquids and Solids Condensed States of Matter Solids, Liquids

Organic prefixes

Prefix number of CMeth 1Eth 2Prop 3But 4Pent 5Hex 6Hept 7Oct 8Non 9Dec 10

Page 22: Liquids and Solids Condensed States of Matter Solids, Liquids

Liquids

•Physical properties of liquids are determined mainly by the nature of their intermolecular forces

Page 23: Liquids and Solids Condensed States of Matter Solids, Liquids

Liquid Properties

•Viscosity▫How easily a liquid flows.▫Karo syrup vs water▫Cold oil vs hot oil

•Surface tension▫beads of water on a newly waxed car▫soap changes surface tension▫meniscus in graduated cylinder

Page 24: Liquids and Solids Condensed States of Matter Solids, Liquids

Surface Tension

•Each water molecule is attracted to its’ neighbor▫In order to move one water▫You have to affect the surrounding

molecules▫The surface doesn’t like to be moved

Has a “tension”

Page 25: Liquids and Solids Condensed States of Matter Solids, Liquids

Solids

•Crystalline solid▫particles exist in a highly ordered,

repeating pattern▫form crystals▫Atoms are organized in pattern. ▫One piece = unit cell▫has definite melting point

Page 26: Liquids and Solids Condensed States of Matter Solids, Liquids

Solids

•Amorphous solids▫“super cooled liquids▫glass, rubber, many plastics▫gets softer and softer as heated

Page 27: Liquids and Solids Condensed States of Matter Solids, Liquids

Solids•Metallic solids - gold, silver•Molecular solids - wax, rubber, plastic•Ionic Solids - sodium chloride•Covalent-network solids - diamond,

graphite

Page 28: Liquids and Solids Condensed States of Matter Solids, Liquids

What is the difference between a liquid and a solid?•Liquid flows and a solid is……

▫Solid•What about the molecules?

▫What is difference about them?•Compare interactions between molecules

▫Solid cannot move from neighbor infant

▫Liquid can move, but cannot go anywhere it wants teenager

▫Gas can go anywhere it wants adult

Page 29: Liquids and Solids Condensed States of Matter Solids, Liquids

Temp

Time

Freezing. Melting Evaporation, Condensation

Solid Liquid Gas

Heating Curve

Page 30: Liquids and Solids Condensed States of Matter Solids, Liquids

Vapor Pressure•What does it mean when something

evaporates?•What does it mean when something boils?•What is vapor pressure?

Page 31: Liquids and Solids Condensed States of Matter Solids, Liquids

Kinetic-Molecular Theory of Gases1.  Gases have mass and consist of really small particles

2. The volume of a gas atom/molecule is very small compared to the distance to the next atom.

 3.  Gases particles are in constant and rapid motion. 4.  Gas particles collide with themselves and walls of

container in an elastic manner. (They have no interaction with each other)

 5.   The average kinetic energy of a gas particle is

related to the temperature. Higher temps mean higher kinetic energy and lower temps mean lower KE.

Page 32: Liquids and Solids Condensed States of Matter Solids, Liquids

Ideal Gases•Follow the kinetic molecular theory•PV = nRT•Assumptions of KMT are not perfect

▫Gases have intermolecular interactions▫The molecules do take up space

•The molecules interact and eventually this interaction is more than the energy it takes to move away. So they condense or freeze.

Page 33: Liquids and Solids Condensed States of Matter Solids, Liquids

Rate of Escape = Rate of Return

Page 34: Liquids and Solids Condensed States of Matter Solids, Liquids

Equilibrium

----time-

Page 35: Liquids and Solids Condensed States of Matter Solids, Liquids

What is Vapor Pressure?•Gas has mass lab

▫Water has a vapor pressure of 17.2 mmHg@20C

•Pressure is the accumulated collisions▫More molecules mean more collisions

•The warmer the water▫The higher the vapor pressure

Page 36: Liquids and Solids Condensed States of Matter Solids, Liquids

Evaporation

•In order for one molecule to escape▫It has to break the intermolecular

attractions▫It has to have enough kinetic energy to

leave▫Why does one molecule have enough

energy to leave and another does not? It has to do with the concept of average

Page 37: Liquids and Solids Condensed States of Matter Solids, Liquids

Temperature and Kinetic Energy

• Particles with KE greater that Emin can evaporate.

• More particles can evaporate at higher temperatures(red and blue areas) than at low temperatures (Blue)

Page 38: Liquids and Solids Condensed States of Matter Solids, Liquids

Real Gases•Why does a gas condense if there is no

interactions between gas molecules?•We said there is an energy involved in

going from a liquid to a gas. What is it called?▫Heat of evaporation.

•What is the energy involved in freezing?▫Heat of fusion

Page 39: Liquids and Solids Condensed States of Matter Solids, Liquids

Atmosphere is exerting pressure or colliding with particles.

When the vapor pressure exceeds atmospheric pressure, it boils

Page 40: Liquids and Solids Condensed States of Matter Solids, Liquids

What is Boiling, Freezing, Melting, Freezing?•Heat of Vaporization▫KJ/mol to go from liquid to gas▫Energy to overcome all intermolecular

interactions

•Heat of Fusion▫KJ/mol to go from liquid to solid▫Energy to be able to move past your

neighbor

Page 41: Liquids and Solids Condensed States of Matter Solids, Liquids

Heat of evaporation is largeCompared to Heat of fusion

Page 42: Liquids and Solids Condensed States of Matter Solids, Liquids

Heating Curve•Energy is exchanged

▫Explain the heating curve in terms of the KMT

▫What happens during the flat parts of the curve?

Temp

Time

Page 43: Liquids and Solids Condensed States of Matter Solids, Liquids

Phase Diagrams

Temperature

Pre

ssu

re

solid

gas

liquid

SublimationDeposition

FreezingMelting Evaporation

Condensation

Super critical fluid

Triple Point

Page 44: Liquids and Solids Condensed States of Matter Solids, Liquids

The Builderspetrochemicals used to make other substances•Alkenes unsaturated

double bonds•Alkynes unsaturated

triple bonds•Cylcoalkanes/enes saturated or

ring of carbons unsaturatedOxygen hydrocarbons saturated or

C, H, Ounsaturated

Page 45: Liquids and Solids Condensed States of Matter Solids, Liquids

Alkenes

Double bond end in eneFollow all rules of naming alkanes plus

number the chain to give the double bond the lowest number possible

Cn H2n

Page 46: Liquids and Solids Condensed States of Matter Solids, Liquids

AlkynesTriple bondEnd in yneFollow all the rules of naming alkanes plusnumber the longest chain to give the triple

bond the lowest number possibleCnH2n-2

Page 47: Liquids and Solids Condensed States of Matter Solids, Liquids

Cyclic compounds

Ring of carbons, no start or finishBegin cyclo – Follow all the rules of namingCnH2n (same as alkenes)

Page 48: Liquids and Solids Condensed States of Matter Solids, Liquids

Oxygenated Hydrocarbons

•All have functional groups▫A atom or group of atoms that give certain

properties to an organic compound

Alcohol, acids, esters, ethers

Page 49: Liquids and Solids Condensed States of Matter Solids, Liquids

Alcohols OHname (-e)+ ol

1-methanol1-ethano1- propanol2-propanol

Page 50: Liquids and Solids Condensed States of Matter Solids, Liquids

Acids COOH

name(-e) + oic acid

Methanoic acidEthanoic acidPropanoic acid

Page 51: Liquids and Solids Condensed States of Matter Solids, Liquids

Water is Weird•Most abundant substance on earth’s

surface•You are 60% water•High heat capacity•High boiling point•Lower density solid than liquid•High surface tension•High heat of vaporization •Universal solvent