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Chapter 13 and 14 Notes
Chapter 13 Solutions and
Chapter 14 Ions in Aqueous Solutions and Colligative Properities
Solution = homogenous
Two parts of a solution
Solute: substance dissolved
Solvent: Substance doing the dissolving.  (Water is the universal solvent)

Types of water solutions
Electrolyte: conducts an electric current (any soluble ionic compound and some polar molecular compounds) ex:  HCl  + H2O =  H30+ , Cl -  forms ions when dissolved in water. (light bulbs glow)
Nonelectrolyte:  does not conduct an electric current  ( Nonpolar molecular) C6H12O6  (light bulb does not glue)

Types of solution
    g-g  =  air;  g-l  =  soft drinks; s-s  =  alloy  (2 or more metals)

Factors affecting rates of Dissolving
Increase surface area (crushing)
Stirring (agitation)
Heating (increases collisions) * reactants must collide to react*

Solubility graph (see table):
Saturated: The exact amount of solute for a volume of solvent at a given temperature.
    (On the line)
Unsaturated: Less solute for a volume of solvent at a given temperature.
    (Below the line)
Supersaturated: More solute for a volume at of solvent a given temperature.
(Above the line)
Factors affecting solubility
Types of solvents and solute "like dissolves like"
    Depends on bonding and intermolecular forces
Immiscible: two liquids not soluble
Miscible: two liquids soluble in each other
Pressure     
Henry's Law: Solubility of a gas in a liquid is directly related to the pressure. (Pressure? gas solubility ?)
***rapid release of gas from a liquid in which it is dissolved***
Temperature
as temp. goes up solubility of gas in a liquid goes down
as temp. goes up solubility of a solid in a liquid goes up

Concentration of Solutions
(Must Know)

   Molarity: The moles of solute divided by 1L solvent.
                           mole
         M=              ________
                            Liter



   % mass      =           mass of solute
                         ___________________________
                     Mass of solute + mass of solvent    


Colligative Properties of Solution
   Freezing point depression, boiling point elevation, know only that the Increased number of dissolved particles elevates the boiling point and depresses the freezing point.  
Ionic compounds have a larger impact on lowering the f.p. and raising the
b.p. (see graph)
Because they produce more dissolved particles than covalent (molecular) substance

Net ionic equations
(NH4)2S(aq)    +   Cd(NO3)2(aq)    ?    NH4NO3(aq)   +    CdS(s)

Cd+2 (aq)   +  2NO-3(aq)  +  2NH+4(aq) +  S-2(aq)  ?  2NH4 + (aq) +  2NO -3(aq)  + CdS(s)
                                                                                                                                 Insoluble                                                      
   
spectator ions are not part of the chemical reactions they do not change into a new substance.  

Specatator ions:
2NO-3(aq)
2NH+4(aq)

The net ionic equation: includes only the ions directly involved with the formation of a new insoluble gas, solid or water.
Cd+2 (aq) +  S-2(aq)  ?   CdS(s)
Ionization: Is the process by which ions are formed from solute molecules by the action of the sovlent .

                                                H2O
HCL         ?         H+1(aq)          +        Cl-1(aq)


H20 (l)       +   HCl(g)           ?         H3O+(aq)      +       Cl -1(aq)




 This is the hydronium ion H3O+(aq)  makes

This is the reason some molecular compounds will form electrolytes
Ex:     HCL
    HBr
   H2SO4
   **all of these are strong electrolytes because all of the H+ ate dissolved**
   an example of an a weak electrolyte is the dissolving of vinegar into water.
   Only 1 of its four H+ are released.