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Chpt 16: Mixtures. Types of Mixtures Colloids & Suspensions Solutions Solubility Electrolytes Percent Concentration Molarity Osmosis Water Purification. Matter. Mixture. Pure Substance. Element. Compound. Fe + S. FeS. Fe. Mg + O 2. MgO. Mg. Classification of matter.
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Chpt 16: Mixtures • Types of Mixtures • Colloids & Suspensions • Solutions • Solubility • Electrolytes • Percent Concentration • Molarity • Osmosis • Water Purification
Matter Mixture Pure Substance Element Compound Fe + S FeS Fe Mg + O2 MgO Mg Classification of matter
Mixture Solution Homogeneous Heterogeneous Pizza Fe + S Gasoline Tea w/ice Sand Mixtures Uniform composition Non-uniformcomposition Suspension Milk Fog Urine Air Peptobismol
Homogeneous Mixtures Colloids & Suspensions • Colloid: Homogeneous mix • But not a solution. Particles larger (10-7 to 10-5 cm) than in a sln (<10-7 cm). But still don’t settle out. Suspension: Heterogeneous mix Large particles may settle out & can be filtered.
Liquid dispersed in Gas = Aerosol Solid in Gas = Aerosol Gas in Liq = foam Liquid in Liquid = emulsion Solid in Liquid = sol Gas in Solid = foam Liquid in Solid = Gel Solid in Solid = solid sol Homogeneous Mixtures Colloids • Gaseous Medium • Fog, • Smoke Liquid Medium Cool whip, milk, paint,blood • Solid Medium • Styrofoam • Jelly,Opals • Pearls, • Concrete
Homogeneous Mixtures Tyndal effect • Colloidal suspensions exhibit light scattering. 1. purple gold sol 2. copper sulfate solution 3. iron(III) hydroxide colloid 1 2 3
Homogeneous Mixtures Solutions • A solution = • A homogeneousmixture that does not scatter light. Sugar in water Saline Oxygen in water Air Dental fillings
Na+ Cl- Na+ Cl- Na+ Cl- Homogeneous Mixtures Solutions • Solvent : • component in greater amount • (The dissolver) • Water • Alcohol • Solute: • component in lesser amount • (The dissolved) • NaCl • Sugar
Homogeneous Mixtures Solutions • solute evenly dispersed • always stays mixed • the solute can’t be filtered out • particles are always in motion • volumesnot additive
Gas in Gas Gas in Liquid Liquid in Liquid Solid in Liquid Liquid in Solid (Hg in Ag) Solid in Solid Homogeneous Mixtures Solutions Gaseous solutions Air, Anesthesia gases Liquid solutions Soda, Vodka, Saline, • Solid solutions • dental fillings, • 14K gold (58% Au ), • Brass (Zn in Cu), • Steel (C in Fe),
d- d- d- d- O O O O d+ d+ d+ d+ d+ H H H H H H H H d+ d+ d+ Hydrogen Bonding of Water Polar Attraction Hydrogen Bonds
Hydrogen Bonding of Water Hydrogen Bonds Causes Surface Tension Surfactants reduce Surface Tension by disrupting H-bonding (soaps, detergents etc.)
Hydrogen Bonding of Water Frozen H2O: Slow moving molecules H-Bond in patterns (Hexagonal Ring Crystals)
Hydration Polar water attracts to Na+ and Cl- ions “Like Dissolves Like” When an ionic solid dissolves in water, the polar solvent removes ions from the crystal lattice.
+ H H O - + H d+ d+ H O d- d- - H - + O d+ d+ H - - - - H H H H H H O O O O O O + + + + H H H H H H Hydration
+ H H O - + H H O - H - + O H - - - - - - - - - - - - - - - H H H H H H H H H H H H H H H O O O O O O O O O O O O O O O + + + + + + + + + + + + + + + H H H H H H H H H H H H H H H Hydration
+ H H O - + H H O - H - + O H - - - - - - - - - - - H H H H H H H H H H H O O O O O O O O O O O + + + + + + + + + + + H H H H H H H H H H H Hydration
+ H H O - + H H O - H - + O H - - - - - - - - - - - - - - - - - - - - - - H H H H H H H H H H H H H H H H H H H H H H O O O O O O O O O O O O O O O O O O O O O O + + + + + + + + + + + + + + + + + + + + + + H H H H H H H H H H H H H H H H H H H H H H Hydration
+ + + + + + + + + + + H H H H H H H H H H H H H H H H H H H H H H O O O O O O O O O O O - - - - - - - - - - - + H H O - H - + O H - - - - - H H H H H O O O O O + + + + + H H H H H Hydration
+ H H O - + H H O - H - + O H - - - - - - - - - - - - - H H H H H H H H H H H H H O O O O O O O O O O O O O + + + + + + + + + + + + + H H H H H H H H H H H H H Hydration
+ + + + + + H H H H H H H H H H H H O O O O O O - - - - - - + H H O - H - + O H - - - - - - - - - - - - - - - - - - - - H H H H H H H H H H H H H H H H H H H H O O O O O O O O O O O O O O O O O O O O + + + + + + + + + + + + + + + + + + + + H H H H H H H H H H H H H H H H H H H H Hydration
+ H H O - + H H O - H H H H H H H H H H H - - - - - - - - - - - + + + + + + + + + + + O O O O O O O O O O O H H H H H H H H H H H - - - - - H H H H H O O O O O + + + + + H H H H H Hydration
+ H H O - + + + + + + + + + + H H H H H H H H H H H H H H H H H H H H O O O O O O O O O O - - - - - - - - - - H - + O H - - - - - H H H H H O O O O O + + + + + H H H H H Hydration
+ H H O - + + + + + H H H H H H H H H H O O O O O - - - - - H H H H H - - - - - + + + + + O O O O O H H H H H - - - - - - - - - H H H H H H H H H O O O O O O O O O + + + + + + + + + H H H H H H H H H Hydration “Like Dissolves Like”
Dissolving covalent compounds • Covalent compounds do not dissociate. • Dilute: • Small amount of solute compared to solvent.
Saturation • Dilute: • Little solute compared to solvent. • Concentrated • Lots of solute compared to solvent • Concentration • Amount of solute • Amount of solution
Saturation • Unsaturated: • Can dissolve more. • Saturated • Have dissolved all possible Undissolved Solids in equilibrium w/ dissolved particles
Saturation • Supersaturated: • Temporarily dissolves more • than normal at given Temp. • Precipitate • Excess solute that falls out of solution
Solubility How muchsolute will dissolve in a solvent • Factors affecting solubility • Polarity • Temperature • Pressure
Polarityvs Solubility Like Dissolves Like Polar Attracts Polar Nonpolar Attracts Nonpolar Ethanol dissolves in H2O NaCl dissolves in H2O But not in C6H14 Oil Oil dissolves in C6H14 But not in H2O H2O
C6H12O6 NaCl C6H12O6 Cl- Na+ C6H12O6 Na+ Cl- Electrolytes Ionic Covalent No Ions Dissolved Ions NaCl Na+ + Cl-
NaCl HF F1- HF Cl- Na+ H+ H+ F1- Na+ Cl- HF Electrolytes Ionic Weak Strong Lots of Ions Only a few Ions NaCl Na+ + Cl- HF H+ + F-
Temperature vs Solubility Gas NaCl Solubility (g/100ml water) Temperature (oC)
Temperature vs Solubility when T increases T Sol • Gases & mostliquids less soluble Solids more soluble T Sol
T S T S T S Temperature vs Solubility The solubility of a gas in a liquid is inversely related to the temperature . If T goes up Gas solubility goes down (gases escape) Gas Solubility
Temperature vs Solubility Carbonated beveragesbottled cold.
Temperature vs Solubility Cold H2O holds more gas than warm H2O If hot rivers lose too much dissolved O2 the fish can’t survive.
P Sol Pressure vs Solubility when P increases • Gases • More soluble Solids & Liquids unaffected Sol P
T P Sol HENRY’S LAW The solubility of a gas in a liquid is directly related to the pressure on the liquid. Gas solubility goes up (more gas will dissolve) If P goes up
T P Sol HENRY’S LAW If P goes down Gas solubility goes down (gases escape) Example: opening a soda. Soda under high pressure Soda under low pressure
The “Bends” Lower P Less dissolved gases Quick ascent Get bubbles in blood & joints extreme pain High P Lots of dissolved N2
The “Bends” Lower P N2accumulates in brain, spinal cord, and peripheral nerves. Bubbles here can cause paralysis and convulsions. Effects often irreversible. Less dissolved gases High P Lots of dissolved gases
The “Bends” Rapid ascent from the high pressure environment to the surface caused the “bends” in these workers. Bends was first discovered in workers who were excavating inside Caissons. CAISSON
Nitrogen Narcosis • “Nitrogen Narcosis”, • = nitrogen euphoria or raptures of the deep. • (Effect somewhat like that observed • when alcohol levels rise in the blood.) So, Helium often substituted for N2 in divers air.
Temperature vs Solubility Divers with bends often packed in ice for transport to hyperbaric chamber.
Soaps & Detergents Temporary Emulsion Emulsifying Agent Oil H2O Stable Emulsion Soaps Detergents Lecithins Polar Head attracts Water Nonpolar Tail attracts Oil
Soaps & Detergents Micelle Oil
Soap Scum Soluble Soap Ca2+, Mg2+, Fe3+ Ions in hard water Ca2+ Ca2+ Insoluble Soap Scum
Ca2+ Cl- CaCO3 CaCO3 Water Purification “Softer”Water Hard Water Na2CO3 Sodium Carbonate (Washing Soda) Cl- Ca2+ Na+ Na+ Cl- Ca2+ Ca2+ Ca2+ Cl- Insoluble Carbonates of Ca2+, Mg2+, Fe3+ can be filtered out Ca2+, Mg2+, Fe3+ Ions in hard water