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Mr. Shields
Learning Objectives – Unit 12
Solutions
Regents Chemistry
1) Describe and be able to give examples of the 3 main types of solutions we’ve discussed in class
a) gas in a liquid, liquid in a liquid, solid in a liquid, gas in a gas
2) Be able to state why all solutions in the Classification of Matter are classified as Homogeneous mixtures
3) Know that Solutions consist of both Solute and Solvent
a) Solutes dissolve in solvents
b) Given a specific solution be able to identify the solute(s) and the solvent
c) For Liquids in Liquids/ gases in gases: Greater volume component is the solvent
d) Everything else: What changes phase is the solute (ex: NaCl (s)  NaCl (aq) or CO2(g)  CO2(aq) )
4) Define the terms miscible and immiscible
a) Used for defining the solubility of liquids in liquids
b) Miscible: Soluble in each other in all proportions
5) Define the terms unsaturated, saturated and supersaturated solution
a) Supersaturated solutions are unstable
b) Supersaturated solutions become saturated solutions when excess dissolved solute crystallizes out
c) Be able to explain how a supersaturated solution can be prepared.
6) Be able to solve Molarity (M) problems for any of the 3 possible unknowns namely, Molarity, Liters of solution or
Moles of solute
a) Given the Mass of the solute be able to convert to moles before solving the Molarity problem.
b) Given the Volume of gas be able to convert to moles before solving the Molarity Problem
7) Be able to solve Molarity (M) by Dilution problems
a) Volume units must be the same on each side of the equation
b) Be able to calculate how much water must be added to reach new Molarity
8) Be able to solve for any variable in the equations for % Concentration (v/v or m/m) and ppm
a) Remember that you are dividing by mass or volume of the SOLUTION
b) Keep units for solute and solution the same
9) Describe how ionic compounds dissolve in water and how the ion-dipole interaction occurs
a) Interactions between polar solutes and polar solvents would be a dipole-dipole interaction (ex. sugar and water)
10) Be able to describe the 3 H values that contribute to the Hsol and whether they are endothermic or exothermic
a) Breaking force of attraction between ions (or molecules) in the solid (endothermic)
b) Breaking intermolecular force of attraction between solvent molecules (H-bonds for water) (endothermic)
c) Formation of dipole-dipole or ion-dipole forces of attraction (exothermic)
11) Identify whether during the dissolving process a solution will become cool or warm based on Hsol
a) –Hsol  solution gets hot
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Mr. Shields
Learning Objectives – Unit 12
Solutions
Regents Chemistry
b) +Hsol  solution gets cold
12) Describe the three factors that effect the Rate of Solution and why they affect the rate
a) Surface area, Temperature, Agitation (Stirring)
13) Be able to describe the effect of polarity, temperature and pressure on the solubility of solids in liquids, liquids
in liquids, or gas in liquids
a) Pressure only affects solubility of gases in liquids according to Henry’s Law.
b) As P inc Solubility increases; Know Henry’s Law
c) As Temp increases the solubility of solids tends to increase but the solubility of gases decrease
14) Be able to predict solubility of non-polar, polar, ionic compounds in polar, non-polar liquids or ethyl alcohol
a) Rule of Thumb “like dissolves like”
b) alcohols have characteristics of both polar & non-polar liquids so they can dissolve both polar and non-polar
solutes but alcohols will not dissolve ionic compounds
c) Alcohols have a both a polar and non-polar portion of the molecule that creates this property
15) Determine how soluble a compound is in H2O at a given temperature using the solubility curves in Table G
16) Use solubility curves to predict how much water is required to dissolve a given amount of solute at a given
temperature or how much solute will dissolve in a given amount of water.
a) Be able to predict the amount of solute that will crystallize from solution when it is chilled
17) Use the curves in Table G to determine whether a solution is unsaturated, saturated or supersaturated
a) Know that when a super saturated solution returns to equilibrium a saturated solution remains
b) Determine whether a compound will be soluble or insoluble in water using the solubility guidelines in Table F.
c)
Know that the table also lists exceptions to the rules
d) Given the reactants of a double replacement rxn predict what the products are and using table F predict whether
the rxn goes to completion due to the formation of a precipitate
18) Define what makes a compound an electrolyte or a non-electrolyte
a) Be able to determine the number of ions a given ionic compound will produce when it dissociates in solution
b) In general, Covalent compounds are non-electrolytes, ionic compounds are electrolytes
19) Define the term Colligative Properties and know that it is the concentration of particles (molecules or ions) that is
important and not what the particle is (ex Cl- and NO3- would both count as 1 particle)
a) Molecules only produce one particle, ionic compounds can produce two or more particles
20) Describe the effects of a non-volatile solute on freezing point and boiling point of a liquid.
a) Freezing point decreases, boiling point increases
b) Know that the effect on freezing pt. and boiling pt. is proportional to the total number of particles in solution
i)
Ex. 1M Na2SO4 has a greater effect than 1M NaCl (3 particles vs 2 at the same concentration)
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Mr. Shields
Learning Objectives – Unit 12
Solutions
Regents Chemistry
ii) Ex 1M KBr has a greater effect than 0.5M KBr (same number of particles but greater concentration
therefore greater number of particles )
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