Factors affecting Solubility Get out your lab to complete it.
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Transcript of Factors affecting Solubility Get out your lab to complete it.
Factors affecting Factors affecting SolubilitySolubility
Get out your lab to Get out your lab to complete itcomplete it
Solutions are MixturesSolutions are Mixtures
The Solution ProcessThe Solution Process
Factors Affecting the Factors Affecting the RateRate of Dissolving of Dissolving
1) 1) Crushing/GrindingCrushing/Grinding
It reduces the particle size It reduces the particle size and and increases the surface increases the surface area area of the solute exposed of the solute exposed to the solventto the solvent
2) 2) Agitation Agitation (stirring) - Brings (stirring) - Brings “fresh” solvent into contact with “fresh” solvent into contact with the solute. (more collisions)the solute. (more collisions)
3) Heating the solvent-3) Heating the solvent- Increases Increases the kinetic energy (moving the kinetic energy (moving faster) of the solvent molecules faster) of the solvent molecules causing causing more frequent collisionsmore frequent collisions between the solvent and solute.between the solvent and solute.
Solubility and Factors Solubility and Factors affecting solubilityaffecting solubility
Solubility-Solubility- the amount of a the amount of a substance required to form substance required to form a saturated solution with a a saturated solution with a specific amount of solvent specific amount of solvent at a specific temp.at a specific temp.
ex: the solubility of sugar in water ex: the solubility of sugar in water is 204 g/100 ml of water at 20is 204 g/100 ml of water at 20ooC.C.
The Solution ProcessThe Solution Process
Consider a sugar solute with a Consider a sugar solute with a solubility (s) of 204 g per solubility (s) of 204 g per 100ml water. The volume in 100ml water. The volume in the diagram is 50 mL. the diagram is 50 mL.
80g/50ml 102 g/50ml 120g/50ml
The Solution ProcessThe Solution Process
1) 1) SaturatedSaturated solution- a solution- a solution that contains the solution that contains the maximummaximum amount of amount of dissolved solutedissolved solute(solubility=204g/100ml)(solubility=204g/100ml)
80g/50ml 102 g/50ml120g/50ml
The Solution ProcessThe Solution Process
2) 2) UnsaturatedUnsaturated solution- a solution- a solution that contains solution that contains lessless solutesolute than a saturated than a saturated solutionsolution (solubility=204g/100ml)(solubility=204g/100ml)
80g/50ml 102 g/50ml 120g/50ml
The Solution ProcessThe Solution Process
3) 3) Supersaturated Supersaturated solution- a solution that solution- a solution that contains contains more solutemore solute than than a saturated solution at the a saturated solution at the same conditionssame conditions (solubility=204g/100ml)(solubility=204g/100ml)
80g/50ml 102 g/50ml 120g/50ml
MiscibiltyMiscibilty
The Solution ProcessThe Solution Process
Different solvents have the Different solvents have the ability to dissolve different ability to dissolve different amounts of solute. amounts of solute.
The key is the nature of the The key is the nature of the solute and the nature of the solute and the nature of the solvent.solvent.
The Solution ProcessThe Solution Process
C. C. “Like dissolves “Like dissolves likelike”- ”-
solubility of a substance solubility of a substance is related to the nature is related to the nature of the solvent. of the solvent.
NATURE OF THE SOLUTENATURE OF THE SOLUTE
POLAR WILL DISSOLVE:POLAR WILL DISSOLVE:
Polar substancesPolar substances Ionic compoundsIonic compounds
NONPOLAR WILL DISSOLVE:NONPOLAR WILL DISSOLVE:
Nonpolar moleculesNonpolar molecules
covalent covalent compoundscompounds
AlcoholsAlcohols
The Solution ProcessThe Solution Process
1) “like dissolves like”- 1) “like dissolves like”- like refers to the like refers to the polarity of polarity of the solute and solventthe solute and solvent
a) ex: water will a) ex: water will dissolve salt because salt dissolve salt because salt is ionic and water is polaris ionic and water is polar
The Solution ProcessThe Solution Process
b) ex: oil will b) ex: oil will not dissolve in not dissolve in water because water because oil is nonpolar oil is nonpolar and water is and water is polarpolar
The Solution ProcessThe Solution Process
miscible miscible (soluble)- (soluble)- Alcohols are Alcohols are miscible in water miscible in water (dissolves in all (dissolves in all proportions) proportions) because they are because they are both polarboth polar
The Solution ProcessThe Solution Process
ImmiscibleImmiscible (not soluble)- (not soluble)- oil is oil is immiscible in immiscible in water.water.
Solvation: Process that Solvation: Process that occurs when a solute occurs when a solute dissolved. Ions or dissolved. Ions or molecules become molecules become completely surrounded by completely surrounded by solvent moleculessolvent molecules
Solubility CurveSolubility Curve
A graph that indicates how A graph that indicates how likely a solute is to dissolve likely a solute is to dissolve in a solvent at any given in a solvent at any given temperature. temperature.
(g solute/100 g solvent) (g solute/100 g solvent)
Solubility Solubility of solidsof solids
The Solution Process The Solution Process (Temperature)(Temperature)
Solubility of a substance is Solubility of a substance is related to related to temperaturetemperature of the of the solutionsolution
Temperature affects solids and Temperature affects solids and gases differently.gases differently.
Solids increaseSolids increase in solubility in solubility
Gases decreaseGases decrease in solubility in solubility
The Solution Process The Solution Process (Pressure)(Pressure)
Solubility of a gas is related to Solubility of a gas is related to pressurepressure being exerted on the being exerted on the solventsolvent
Pressure Pressure onlyonly affects the affects the solubility of solubility of gasesgases. Solubility . Solubility of liquids and solids is not of liquids and solids is not changed by changes in changed by changes in pressure.pressure.
a) Reason for sodas a) Reason for sodas “bubbling up” when “bubbling up” when the top of a soda the top of a soda bottle is open. bottle is open.
When the bottle is When the bottle is opened, there is a rapid opened, there is a rapid decrease in the decrease in the pressure and the pressure and the solubility of carbon solubility of carbon dioxide gas in the water dioxide gas in the water is greatly reduced is greatly reduced causing the familiar causing the familiar bubbling and foaming. bubbling and foaming.
b) This rapid escape of a b) This rapid escape of a gas from a liquid is called gas from a liquid is called
effervescenceeffervescence..
E. Solubility of E. Solubility of a substance is a substance is related to related to temperaturetemperature of the solvent.of the solvent.
1) Gases will 1) Gases will always have always have greater greater solubility in solubility in cold cold solvents.solvents.
Types of Mixtures: SolutionsTypes of Mixtures: SolutionsIonic solutions- solutions Ionic solutions- solutions composed of ions that are free to composed of ions that are free to move throughout the solutionmove throughout the solutiona)a)ElectrolyteElectrolyte- Can conduct an - Can conduct an electric current;electric current; acids, bases & saltsacids, bases & saltsEx: NaCl in waterEx: NaCl in waterEx: Tap waterEx: Tap water
Solutions in which the solute is Solutions in which the solute is composed of neutral molecules composed of neutral molecules
Non-electrolyteNon-electrolyte- cannot conduct - cannot conduct electric currents; covalent electric currents; covalent compounds (exceptcompounds (except
acids)acids)Ex: Sugar in pure waterEx: Sugar in pure water
The Solution ProcessThe Solution Process
Water molecules are in Water molecules are in continuous motioncontinuous motion..
When a solute is added When a solute is added the water molecules the water molecules will will collidecollide with it. with it.
The Solution ProcessThe Solution Process
The water molecules The water molecules attractattract the solute particles the solute particles and the particles will and the particles will break break awayaway..
The Solution ProcessThe Solution Process
SolvationSolvation: The process that : The process that occurs when a solute occurs when a solute dissolvesdissolves– ions or molecules become ions or molecules become solvated solvated or surrounded by or surrounded by solvent moleculessolvent molecules