Ch. 12: Solutions CP Chemistry Mrs. Klingaman

1. Define Soluble- Capable of being dissolved 2. Define Solution- A homogeneous mixture of two or more substances uniformly dispersed through a single phase

3. Define Solvent- The dissolving medium in the solution 4. Define Solute- The substance being dissolved in the solution

lesser 5. The solute is designated as the component of a solution that is of ________ quantity.

6. Solutions may exist as ______, ________, or _______. gases liquids solids Solute StateSolvent StateExample Gas O 2 (g) in N 2 (g) GasLiquidCO 2 (g) in H 2 O (l) Liquid rubbing alcohol (l) in H 2 O (l) LiquidSolidHg (l) in Ag (s) & Sn (s) – dental amalgam SolidLiquidSugar (s) in H 2 O (l) Solid Cu (s) in Ni (s)

7. Give an example of an alloy and list the properties of that alloy that make it more desirable than the individual pure metal from which it is composed Brass (Zn & Cu) Sterling Silver (Ag & Cu) Desirable Properties: - more strength - greater resistance to corrosion

8. Define Suspension- Particles in a solvent that are so large that they settle out of the solution unless the mixture is constantly stirred or agitated Ex: jar of muddy water

9. Define Colloid - Particles that are of intermediate size between those in solutions and suspensions a) an emulsion is a liquid in a liquid example of a colloid (milk) b) clouds and fog are examples of colloids called liquid aerosols in which a liquid is dispersed in a gas c) Foam is a type of colloid in which a gas is dispersed throughout a liquid d) A sol is a type of colloid in which a solid is dispersed throughout a liquid (ex: paint)

10. Define Tyndall effect - Light is scattered by colloidal particles in a transparent medium The Tyndall effect can be used to distinguish a solution from a colloid (colloids will scatter light making a beam visible)

11. Define Brownian Motion- Under a microscope, the tiny particles in a colloid are in motion due to collisions of rapidly moving particles suspended in a fluid

12. Figure 1.7 – Properties of solutions, suspensions, and colloids SolutionsColloidsSuspensions homogeneousheterogeneous particle size: 0.01 – 1 nm particle size: 1 – 1000 nm particle size: over 1000 nm Do NOT separate upon standing Particles settle out after standing Can’t be separated by filtration CAN be separated by filtration Do NOT scatter lightScatter light (Tyndall effect) May scatter light but are not transparent

Types of Mixtures Activity (a) Solution, (b) Suspension, or (c) Colloid ____ - particles in a solvent that are of intermediate size; solution scatters light; does not separate & cannot be filtered ____ - homogeneous mixture of 2+ substances in a single phase; solution does not scatter light; does not does not separate & cannot be filtered ____- particles in a solvent are so large that they settle out upon standing; solution may scatter light; solution can be separated by filtration c a b

13. Define Electrolyte A substance that dissolves in water to give a solution which conducts electricity (NaCl, soluble ionic compounds, acids, bases) 4. Define Nonelectrolyte A substance that dissolves in water to give a solution that does not conduct an electric current (sugar, soluble covalent compounds)

Factors that Affect Solubility - Solids Packet pg. 5 1)“Like-dissolves-Like”– polar solvents dissolve polar (and ionic) solutes and, nonpolar solvents dissolve nonpolar solutes

Factors that Affect Solubility - Solids Packet pg. 5 2) Surface Area of Solute – increasing the surface area of solute exposed to the solvent increases solubility (crushing up a solid; sugar cube vs. granulated sugar)

Factors that Affect Solubility - Solids Packet pg. 5 3) Stirring/Agitation– movement of the solute will have same effect as increasing the surface area exposed to the solvent = increased collisions = increased solubility

Factors that Affect Solubility - Solids Packet pg. 5 4) Temperature – Increased temperature increases the solubility of a solid (or liquid) because the KE is increased = molecules moving faster = more collisions between solute & solvent

Factors that Affect Solubility - Gases Packet pg. 5 1)Pressure– Increases pressure on a gas increases its solubility in a liquid (forces gas particles closer to liquid solvent so that they can interact together

Factors that Affect Solubility - Gases Packet pg. 5 2) Temperature– LOWER temperatures increase gas solubility – this slows down the gas particles so they can interact with the liquid solvent

Factors that Affect Solubility - Gases Packet pg. 5 3) Molecular Size– The larger the gas molecule (larger molar mass) the greater the solubility of the gas in a liquid solvent (greater intermolecular forces of attraction)

Types of Solutions Saturated  A solution that contains the maximum amount of dissolved solute

Types of Solutions Unsaturated  A solution that contains less than a saturated solution under existing conditions

Types of Solutions Supersaturated  A solution that contains more dissolved solute than a saturated solution contains under the same conditions

Solubility Curves – pg. 6 Solubility  The amount of that substance required to form a saturated solution with a specific amount of solvent at a specified temperature

1. Colligative Properties Definition: – Properties of a solution which depend on the concentration of solute particles present in the solution but NOT on the identity of the solute particles. There are 4 colligative properties!

1) Vapor Pressure Lowering When a solute is dissolved into a solvent, the vapor pressure above a liquid is decreased (lowered)

2) Boiling Point Elevation Adding a solute to a pure solvent will increase (or elevate) the temperature at which the solution boils  Ex) adding salt to water when boiling pasta  H 2 O BP = 100ᵒC  H 2 O + NaCl BP = 102ᵒC

3) Freezing Point Depression Adding a solute to a pure solvent will decrease (or depress) the temperature at which the solution freezes (or melts)  Ex) adding salt to icy roads  Ex) adding antifreeze to car radiators.  H 2 O (ice) FP = 0ᵒC  H 2 O + NaCl FP = –1.2ᵒC

4) Osmotic Pressure ( π ) The pressure required to stop osmosis 3. Osmosis The diffusion of water (or another solvent) from the more dilute solution (less mols solute) to the more concentrated solution (more mols solute)

Osmosis (dilute solution)

Osmosis in Blood Cells Hypertonic- – Solution outside the cell is more concentrated than the solution inside of the cell Water will flow out of the cell, and it will shrivel. This is what happens when you are dehydrated!!!

Osmosis in Cells Hypotonic- – Solution outside the cell is less concentrated than the solution inside of the cell Water will flow into the cell eventually causing it to rupture.