Unit 11 – States of Unit 11 – States of Matter & Solutions Matter & Solutions Chapter 13.2-13.4 & Chapter 13.2-13.4 & Chapter 15 Chapter 15 Unit Test: March 13th Unit Test: March 13th
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!!