# Solutions

 What is an ideally dilute solution? 1. Both solute & solvent have similar properties 2. Solute molecules are separated from one another by being surrounded completely by solvent molecules   What are colloids? 1. Type of solution 2. CANNOT be separated by filtration 3. Scatter light 4. Solute particles do not settle out of solution   How can colloids be separated? 1. Dialysis (i.e. use of semipermeable membrane)2. Charge separation 3. Filtration AFTER heating   What happens when colloids are heated? Solute particles coagulate and can be separated via filtration  What bonds are implicated in polar vs. nonpolar solutions? Polar: dipole-dipole Non-polar: London Dispersion Forces   Is water a good conductor of electricity? Not normally, but when it contains electrolytes it is  List five ways to measure [] 1. Molarity 2. Molality 3. Mole fraction 4. Mass percentage 5. Parts per million   3 Steps in forming a solution  1. Breaking intermolecular bonds between solute molecules (+H)2. Breaking intermolecular bonds between solvent molecules (H+)3. Making intermolecular bonds between solute and solvent molecules (-H) What happens to entropy when solutions form?   Entropy always increases when solutions form  What is a nonvolatile solute? 1. Does not contribute to vapor pressure2. Consumes surface area of liquid and thus, reduces vapor pressure by limiting the amount of solvent molecules that can escape into a gas -- so affects the overall vapor pressure of the solution, but indirectly  What is a volatile solute? 1. Contributes to a solution's vapor pressure2. Competes for the surface area *Sum of partial pressure of each contributor of solution will give total vapor pressure of the solution  Deviation from Raoult's law for a non-ideal solution  If Hsoln is negative: stronger bonds have been formed so vapor pressure will be lower than predicted  If Hsoln is positive: weaker bonds have formed so vapor pressure will be higher than predicted  What is the opposite of dissolution? Percipitation  Saturated solution Rate of dissolution = Rate of percipitation  Adding any more solute will form a percipitate Equilibrium of a solvation reaction Ksp ; same as Keq except specialized to a solution ; called the solubility product  This is a constant value that can be found in a book  Remember to leave out pure solids and liquids Changes with temperature ONLY What is Solubility? The solubility of something in a given solvent  AKA the maximum number of moles that can dissolve in a solution Changes with temperature and ions present  What are spectator ions? Ions in a solution that have no effect on the equilibrium constant AKA the solubility product  How are the [] of the solute and solvent in a saturated soln? A saturated solution is at equilibrium, meaning that the maximum moles of solute have been able to dissolve in the given solvent.  1. The [] of solute is at a maximum, any more solute added would push this reaction backwards and percipitate will form 2. The [] of the solvent is at a minimum because the solute's [] is maximized Partial pressures always add up to give total pressure Authorhellosleepy ID159364 Card SetSolutions DescriptionMCAT General Chemistry Updated2012-06-19T19:06:58Z Show Answers