Unit 11 – States of Matter Unit 11 – States of Matter & Solutions& Solutions

Chapter 13.2-13.4 & Chapter Chapter 13.2-13.4 & Chapter 1515

Unit Test: March 13thUnit Test: March 13th

VocabularyVocabulary

• CohesiveCohesive

• CrystallineCrystalline

• AmorphousAmorphous

• DiffusionDiffusion

• Dynamic equilibriumDynamic equilibrium

• VolatileVolatile

KMT ReviewKMT Review

• All particles are in All particles are in motion unless they are motion unless they are at absolute zeroat absolute zero

• Kinetic energyKinetic energy increases increases with temperaturewith temperature– Particles move faster and Particles move faster and

farther apartfarther apart• Applies to all states of Applies to all states of

matter - solids, liquids, matter - solids, liquids, and gasesand gases

• Ex: concrete expanding Ex: concrete expanding on highwayson highways

Intermolecular ForcesIntermolecular Forces• InterInter- means “between” or - means “between” or

“among”“among”• Intermolecular forces hold Intermolecular forces hold

two molecules togethertwo molecules together– Ex:Water in a drop, carbon Ex:Water in a drop, carbon

and cellulose (aka. pencil and cellulose (aka. pencil lead & paper)lead & paper)

• Weak intermolecular Weak intermolecular forcesforces– Low boiling pointsLow boiling points– Most likely in gaseous stateMost likely in gaseous state

• Strong intermolecular Strong intermolecular forcesforces– High boiling pointsHigh boiling points– Most likely in solid stateMost likely in solid state

States of Matter - SolidsStates of Matter - Solids• Orderly, rigid and cohesive at the molecular levelOrderly, rigid and cohesive at the molecular level• Definite shape & volumeDefinite shape & volume• Particles vibrate around fixed pointsParticles vibrate around fixed points• Structure may be Structure may be crystallinecrystalline or or amorphousamorphous

Crystalline Crystalline Structure:Structure:Particles arranged in Particles arranged in an orderly, repeating an orderly, repeating 3D pattern3D pattern

Amorphous Structure:Amorphous Structure:Forms when molten material cools Forms when molten material cools too quickly for crystals to form; no too quickly for crystals to form; no definite repeating patterndefinite repeating pattern

States of Matter - LiquidsStates of Matter - Liquids• Cohesive but not ordered or rigidCohesive but not ordered or rigid• Definite volume, take shape of containerDefinite volume, take shape of container• Particles vibrate around Particles vibrate around movingmoving points points• Have Have fluidityfluidity (ability to flow) (ability to flow)

– Process of movement refered to as Process of movement refered to as diffusiondiffusion– Liquids will diffuse through other liquids at a slower rate Liquids will diffuse through other liquids at a slower rate

than gases diffusing than gases diffusing – Ex: water leak vs. gas leak in a houseEx: water leak vs. gas leak in a house

Diffusion of red food coloring through water

States of Matter - LiquidsStates of Matter - Liquids• ViscosityViscosity – measure of resistance – measure of resistance

to flowto flow– Strong IMF = high viscosityStrong IMF = high viscosity– Molasses have a high viscosity Molasses have a high viscosity

(resists flow)(resists flow)– Water has a low viscosity (flows Water has a low viscosity (flows

easily)easily)• Vapor PressureVapor Pressure – pressure – pressure

exerted by vapor molecules exerted by vapor molecules above a liquid when dynamic above a liquid when dynamic equilibrium is reachedequilibrium is reached– Depends on temperature (Depends on temperature (T VP)– Also depends on strength of IMF Also depends on strength of IMF

((IMF VP)• Compare the diagram of water Compare the diagram of water

and alcoholand alcohol– What do the arrows mean?What do the arrows mean?– Which would have a stronger IMF?Which would have a stronger IMF?

Vapor

Water Alcohol

Vapor

States of Matter - LiquidsStates of Matter - Liquids• Vapor pressure Vapor pressure

graphs show vapor graphs show vapor pressure vs. pressure vs. temperaturetemperature

• Standard pressure is Standard pressure is 1 atm or 101.3 kPa – 1 atm or 101.3 kPa – indicated by the dark, indicated by the dark, horizontal linehorizontal line– Intersection of curved Intersection of curved

lines and standard lines and standard pressure is the normal pressure is the normal boiling pointboiling point

States of Matter - LiquidsStates of Matter - Liquids

• Dynamic equilibriumDynamic equilibrium - 2 - 2 opposite processes occurring at opposite processes occurring at the same ratethe same rate– Ex: evaporation and condensationEx: evaporation and condensation

• VolatilityVolatility – how easily a fluid – how easily a fluid evaporates, they have:evaporates, they have:– High vapor pressureHigh vapor pressure– Low IMFLow IMF– Low boiling pointsLow boiling points– Examples: alcohol, acetone, Examples: alcohol, acetone,

ammoniaammonia

States of MatterStates of Matter

States of Matter – Phase States of Matter – Phase ChangesChanges

• Melting/FreezingMelting/Freezing– changes between solid and changes between solid and

liquid phasesliquid phases

• Vaporization/Vaporization/CondensationCondensation– changes between liquid and changes between liquid and

gas (vapor) phases gas (vapor) phases

• Sublimation/DepositionSublimation/Deposition– change directly from solid change directly from solid

to gas or vice versato gas or vice versa– Ex: Dry ice, solid air Ex: Dry ice, solid air

fresheners, iodinefresheners, iodine

States of Matter – Phase States of Matter – Phase ChangesChanges

States of Matter – Phase States of Matter – Phase ChangesChanges

• EndothermicEndothermic phase phase changes absorb energychanges absorb energy– SublimationSublimation– VaporizationVaporization– MeltingMelting

• ExothermicExothermic phase phase changes release energychanges release energy– DepositionDeposition– CondensationCondensation– FreezingFreezing

States of Matter – Phase States of Matter – Phase ChangesChanges• Vaporization may be due to:Vaporization may be due to:

– EvaporationEvaporation• Only occurs at the surface of the liquid at room temperatureOnly occurs at the surface of the liquid at room temperature• Cooling process for the human body (sweating)Cooling process for the human body (sweating)

– BoilingBoiling• Occurs throughout the liquidOccurs throughout the liquid• Boiling point occurs when Vapor Pressure=Atmospheric Boiling point occurs when Vapor Pressure=Atmospheric

PressurePressure– Higher altitudes have lower atmospheric pressureHigher altitudes have lower atmospheric pressure– Would the boiling point increase or decrease?Would the boiling point increase or decrease?– Would it take a longer or shorter time to cook food?Would it take a longer or shorter time to cook food?

States of Matter - Phase ChangesStates of Matter - Phase Changes

• During phase changes, there is no change in kinetic energy - During phase changes, there is no change in kinetic energy - only potential energy increases!!!only potential energy increases!!!– Liquid HLiquid H22O at 0O at 0ooC has more kinetic energy than solid HC has more kinetic energy than solid H22O at 0O at 0ooCC

– Gas HGas H22O at 100O at 100ooC has more kinetic energy than liquid HC has more kinetic energy than liquid H22O at 100O at 100ooCC

Coke on ice - shows 3 phases of matter

States of Matter – Phase States of Matter – Phase ChangesChanges

States of Matter – Phase States of Matter – Phase ChangesChangesPoints you must be able to identify:Points you must be able to identify:• Standard PressureStandard Pressure

– Line at 1 atm or 101.3 kPaLine at 1 atm or 101.3 kPa

• Normal Freezing PointNormal Freezing Point– Temp at which standard pressure meets the solid-liquid Temp at which standard pressure meets the solid-liquid

curve curve

• Normal Boiling PointNormal Boiling Point– Temp at which standard pressure meets the liquid-vapor Temp at which standard pressure meets the liquid-vapor

curvecurve

• Triple PointTriple Point– Pressure and temperature where all three phases coexistPressure and temperature where all three phases coexist

• Critical PointCritical Point– Pressure and temperature at which a liquid can no longer Pressure and temperature at which a liquid can no longer

existexist

Heterogeneous MixturesHeterogeneous Mixtures• Heterogeneous MixtureHeterogeneous Mixture: two or more : two or more

substances physically combined; not substances physically combined; not uniform throughoutuniform throughout

• Ex: Granite, chex mixEx: Granite, chex mix

Unique Properties of WaterUnique Properties of Water

• Hydrogen bonding Hydrogen bonding between water between water molecules causes:molecules causes:– High boiling and melting High boiling and melting

pointspoints– Ability to hold a large Ability to hold a large

amount of heatamount of heat– High surface tensionHigh surface tension– Droplets to be sphericalDroplets to be spherical

• Water is…Water is…– Polar moleculePolar molecule– Universal solventUniversal solvent– Vital for human lifeVital for human life

• HydrationHydration• Transportation of wasteTransportation of waste

to the kidneysto the kidneys

Unique Properties of WaterUnique Properties of Water

SolutionsSolutions

• Homogeneous mixtures of Homogeneous mixtures of solids, liquids and/or gasessolids, liquids and/or gases

• Composed of:Composed of:– Solute – substance being Solute – substance being

dissolved (smaller amount)dissolved (smaller amount)– Solvent – substance that does Solvent – substance that does

the dissolving (the larger the dissolving (the larger amount)amount)

– Identify the solute and Identify the solute and solvent:solvent:• 50 g NaCl and 100 mL water50 g NaCl and 100 mL water• 75 mL water and 100 mL alcohol75 mL water and 100 mL alcohol• 20 mL CO20 mL CO22 in 50 mL water in 50 mL water

SolutionsSolutions

• Rate of Solution – how fast a solute will dissolve Rate of Solution – how fast a solute will dissolve in a solventin a solvent– Increased by heating, stirring and grinding (crushing)Increased by heating, stirring and grinding (crushing)

SolutionsSolutions

• SolubilitySolubility – the amount of solute – the amount of solute that will dissolve in a solvent at a that will dissolve in a solvent at a certain temperature and pressurecertain temperature and pressure

• SolubleSoluble: like dissolves like: like dissolves like– Polar or Ionic solutes dissolve in polar Polar or Ionic solutes dissolve in polar

solventssolvents• Areas of charge are attracted to one anotherAreas of charge are attracted to one another• Ex: water, alcohol, sugar, saltEx: water, alcohol, sugar, salt

– Non-polar solutes dissolve in non-polar Non-polar solutes dissolve in non-polar solventssolvents• No charges so there is no attractionNo charges so there is no attraction• Ex: oils, gasoline, diatomic molecules (H O F Ex: oils, gasoline, diatomic molecules (H O F

Br I N Cl)Br I N Cl)

• InsolubleInsoluble: do not dissolve in each other: do not dissolve in each other– Polar and non-polarPolar and non-polar

• Ex: oil and waterEx: oil and water

Solutions - SolubilitySolutions - Solubility• Polar vs. Non-polar Molecules:Polar vs. Non-polar Molecules:

•Non-polar moleculesNon-polar molecules have have charges that are evenly charges that are evenly distributed, due to shape (ex: any distributed, due to shape (ex: any diatomic molecule, gasoline)diatomic molecule, gasoline)

•Polar moleculesPolar molecules have a have a partial positive and a partial partial positive and a partial negative charge (ex: water)negative charge (ex: water)

Solutions - SolubilitySolutions - Solubility

SolutionsSolutions

• Factors that affect solubilityFactors that affect solubility– TemperatureTemperature

• Solids: ↑ temp ↑ solubilitySolids: ↑ temp ↑ solubility• Gases: ↑ temp ↓ solubiltyGases: ↑ temp ↓ solubilty

– Fish “breathe” dissolved OFish “breathe” dissolved O22 through their gills. Why would through their gills. Why would thermal pollution kill fish?thermal pollution kill fish?

– PressurePressure• Affects gases only!Affects gases only!• ↑ ↑ pressure ↑ solubilitypressure ↑ solubility

– Carbonated drinks such as soda Carbonated drinks such as soda contain the gaseous solute CO2 contain the gaseous solute CO2 and are bottled under pressure. and are bottled under pressure. Why do bubbles form in soda?Why do bubbles form in soda?

SolutionsSolutions• Types of solutionsTypes of solutions

– UnsaturatedUnsaturated – contains less solute than the solution is – contains less solute than the solution is able to holdable to hold• If you add more solute it would dissolveIf you add more solute it would dissolve

– SaturatedSaturated – contains the maximum amount of solute it – contains the maximum amount of solute it can holdcan hold• If you add more solute it would fall to the bottomIf you add more solute it would fall to the bottom

SolutionsSolutions• SupersaturedSupersatured – holds more solute than it should – holds more solute than it should

at the given temperatureat the given temperature– Made by heat the solvent to dissolve all the material Made by heat the solvent to dissolve all the material

then slowly cooling it downthen slowly cooling it down– Adding more solute would cause ALL of the solute to fall Adding more solute would cause ALL of the solute to fall

out of solutionout of solution• Supersaturated sodium acetate solutionSupersaturated sodium acetate solution

SolutionsSolutions

• Solubility graphs Solubility graphs show amt of solute show amt of solute vs. temperaturevs. temperature– Above the curve Above the curve

would be would be supersaturatedsupersaturated

– The curve itself is at The curve itself is at saturationsaturation

– Below the curve Below the curve indicates unsaturated indicates unsaturated solutionssolutions

– Negative (downward) Negative (downward) slope indicates a gasslope indicates a gas

Solutions - Colligative Solutions - Colligative PropertiesProperties• Physical properties of solutions Physical properties of solutions

that depend on the concentration that depend on the concentration of the particles in the solution. of the particles in the solution. Colligative properties include:Colligative properties include:– Boiling point elevation (vapor Boiling point elevation (vapor

pressure lowering)pressure lowering)• Adding salt to water for cookingAdding salt to water for cooking

– Freezing point depressionFreezing point depression• Adding salt to ice to make ice Adding salt to ice to make ice

creamcream• Antifreeze in carsAntifreeze in cars• Salting roads in the winterSalting roads in the winter

– Osmotic pressureOsmotic pressure• Responsible for plant cell wall Responsible for plant cell wall

sturdinesssturdiness• Adding salt to spinach when Adding salt to spinach when

cooking decreases the pressure cooking decreases the pressure and the cell releases the water and the cell releases the water causing the spinach to wiltcausing the spinach to wilt

Solutions - Colligative Solutions - Colligative PropertiesProperties• How does adding a solute How does adding a solute

change physical properties?change physical properties?– Solute particles get in the way Solute particles get in the way

of the solvent moleculesof the solvent molecules– Makes it harder for the Makes it harder for the

solvent molecules to go into solvent molecules to go into the vapor phase (more energy the vapor phase (more energy needed – higher temp)needed – higher temp)

– Makes it harder for the Makes it harder for the solvent molecules to freeze solvent molecules to freeze (need to release more energy (need to release more energy – lower temp)– lower temp)

Solutions - ConcentrationSolutions - Concentration• Amount of solute dissolved in a given amount of Amount of solute dissolved in a given amount of

solventsolvent• Qualitative descriptions:Qualitative descriptions:

– Dilute – solution containing a small amount of soluteDilute – solution containing a small amount of solute– Concentrated – solution containing a large amount of soluteConcentrated – solution containing a large amount of solute

Solutions - ConcentrationSolutions - Concentration

• Quantitative descriptions:Quantitative descriptions:– Molarity (M): # mol solute Molarity (M): # mol solute

dissolved in 1 L of solutiondissolved in 1 L of solutionM = mol soluteM = mol solute

L solnL soln

– Ex. IV medicines have their Ex. IV medicines have their concentration calculated concentration calculated before they are before they are administeredadministered

Solutions - ConcentrationSolutions - Concentration

1.1. What is the molarity of 2 mol NaCl in 5 L of What is the molarity of 2 mol NaCl in 5 L of solution?solution?

2.2. How many moles of KBr would be present in 1 L of a How many moles of KBr would be present in 1 L of a 3M solution?3M solution?

3.3. What is the volume of a 1.5M solution of HCl that What is the volume of a 1.5M solution of HCl that contains 10 moles of HCl?contains 10 moles of HCl?

4.4. What is the molarity of 2000 mL water containing What is the molarity of 2000 mL water containing 49 g H49 g H33POPO44??

Solutions - ConcentrationSolutions - Concentration• Dilutions Dilutions

– Adding more solvent to a solution spreads the Adding more solvent to a solution spreads the solute through a larger volumesolute through a larger volume

MM11VV11 = M = M22VV22

MM1 1 = initial molarity= initial molarity M M2 2 = final molarity= final molarity

VV1 1 = initial volume= initial volume V V2 2 = final volume= final volume

Solutions - ConcentrationSolutions - Concentration

1.1. 100 mL of a 3 M solution of NaOH is 100 mL of a 3 M solution of NaOH is diluted to 375 mL. What is the new diluted to 375 mL. What is the new molarity?molarity?

2.2. How much 12 M HCl would be How much 12 M HCl would be required to make 35 mL of 0.5 M required to make 35 mL of 0.5 M HCl solution?HCl solution?

End of Unit 11 NotesEnd of Unit 11 Notes

Study for the Test on March Study for the Test on March 1313thth!!