CP Chapter 15/16 Solutions
What Are Solutions?
What is a solution?
 A solution is uniform ___________________ that may contain solids, liquids, or gases.
 Known as a _____________________ mixture
 Solution = ________________ + ____________________
o Solvent – The substance in ______________________ abundance in the solution
 A solvent dissolves the solute. (dissolving ___________________)
o Solute – The substance dissolved in the solvent
Characteristics of Solutions
 Soluble – The solute’s ability to ____________________ in a solvent
 Insoluble – The solute is ______________ able to dissolve in a solvent
 Immiscible – Two liquids that can be mixed together, but _________________ shortly after
you stop mixing them
 Miscible – Two liquids that are ____________________ in each other
Solvation in Aqueous Solutions
 Solvation – The process of ___________________ solute particles with solvent particles to
form a solution
 Aqueous solution – A solute dissolved in __________________
Rules for Solvation
 _________ dissolves __________
 Polar molecules dissolve _______________ molecules
 _______________ molecules dissolve non-polar molecules
Factors that Affect Rate of Solvation
 Need to increase ___________________________ between solute and solvent molecules
1. Agitating the mixture (__________________________)
 New collisions between solute and solvent will occur
2. Increasing the surface __________________ of the solute (Crushing the solute)
 Greater surface area allows more collisions to occur
3. Increasing the __________________________ of the solvent
 Increases kinetic energy of molecules and more frequent collisions occur
4. Increasing the ________________________ (For gases)
 Increases the rate of collision between particles.
Solubility
 Solubility – The ________________________ amount of solute that will dissolve in a given
amount of solvent at a specified temperature and pressure.
 Solubility is usually expressed in grams of solute per 100 g of solvent or in
_______________________.
 Saturated solution contains the _____________________ amount of dissolved solute for a
given amount of solvent at a specific pressure and temperature.
 Unsaturated solution contains ____________ dissolved solute for a given temperature and
pressure than a saturated solution
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
Supersaturated solution contains ________________ dissolved solute than a saturated
solution at the same temperature
Factors That Affect Solubility
 Temperature
o Most substances as temperature increases solubility _______________________
o __________________ are the exception and solubility tends to decrease as
temperature increases, because they are moving quickly escaping the solvent
 Pressure
o The solubility of a gas in any solvent increases as the __________________ above the
solution increases, keeping the gas from escaping in the solvent
Example 1:
If the solubility of NaCl at 25oC is 36.2 g/100 g H2O, what is the maximum mass of NaCl can
be dissolved in 200.0 g of H2O at the same temperature?
Example 2:
If the solubility of KNO3 at 20oC is 79 grams in 250 grams of water, what is solubility in grams
per liter?
Henry’s Law
 Henry’s Law states that at a given temperature the solubility (S) of a gas in a liquid is directly
proportional to the pressure (P)
Example 3:
The solubility of a gas is 0.35 g/L at 25.0 kPa of pressure. What is the solubility when the
pressure is increased to 115 kPa?
Electrolytes
 Electrolytes are compounds that ________________ or ionize in water to form a solution that
conducts an electric current
 Ionic compounds are _____________________ because they dissociate into ions
 Ex: NaCl(s) → Na+ + Cl–
 Electrolytes dissociate into individual ions and conduct an _________________ current
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Strong and Weak Electrolytes
 A strong electrolyte conducts a ____________________ current and the compound has
completely dissociated into ions
o NaCl
 A weak electrolyte conducts a _____________________ current because only part of the
solute exists as ions.
o NH3 (Ammonia)
 A nonelectrolyte does ____________ dissociate or form ions, thus does not conduct a
current.
o Most molecular compounds are nonelectrolytes
o Sucrose (sugar)
Solution Concentrations
Percent by mass
Solution = Solute + Solvent
Example 1: An aquarium must contain 13.6 g NaCl per 100.0 g of water. What is the percent by
mass (m/m) of NaCl in the solution?
Example 2: You have a 650.0 g of a KCl solution. If the percent by mass of the solute, KCl is 1.25%
(m/m), how many grams of solute are in the solution? How many grams of solvent are in the
solution?
Percent by volume
Example 3: What is the percent by volume (v/v) of ethanol in a solution that contains 45 ml of ethanol
dissolved in 145 ml of water?
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Example 4: If you have 200.0 mL of a 35.0% aqueous solution of ethanol, what volume of ethanol and
water are in the solution?
Parts Per Million (ppm)
1 ppm = 1 mg/L
Example 5: If 25 grams of a chemical is dissolved in 75 grams of water, what is the concentration of
the chemical in parts per million (ppm).
Example 6: Suppose 17 grams of sucrose is dissolved in 183 grams of water. What is the
concentration of sucrose in ppm?
Example 7: 150 mL of an aqueous sodium chloride solution contains 0.0045 g NaCl. Calculate the
concentration of NaCl in parts per million (ppm). 1 ppm = 1 mg/L
Example 8: Convert 0.0035% NaCl by mass into parts per million of NaCl.
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Molarity
Unit for molarity
Example 1: Calculate the molarity of 1.75 L solution containing 3.45 moles of CaCl2.
Example 2: Calculate the molarity of an 855 mL solution containing 2.75 moles of NaNO3.
Example 3: A 0.1005 L of IV solution contains 5.10 g of glucose. What is the molarity of this solution?
The molar mass of glucose is 180.18 g/mol.
Example 4: How many moles of HCl are in a 0.85 L of a 0.50 M solution?
Example 5: How many moles of NaNO3 are in 655 mL of a 3.45 M solution?
Preparing Molar Solutions
Example 1: How many grams of CaCl2 would be dissolved in a 2.5L of a 0.10 M solution of CaCl2?
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Example 2: How many grams of NaOH are in 2.5 L of 4.0 M NaOH solution?
Example 3: How many grams of NaOH are in 350 mL of a 2.3 M solution?
Diluting Solutions
Example 1: What volume, in milliliter of 2.00M CaCl2 stock solution would you use to make 0.50L of
0.300 M calcium chloride solution?
What volume in milliliters of a 12.0 M HCl solution would you use to make 2.50 L of a 2.00 M HCl
solution?
Colligative Properties
 The physical properties of solutions that are different than
the physical properties of a pure solvent. These depend
only upon the number of particles in a solution.
o Vapor pressure lowering
o Boiling point increasing
o Freezing point lowering
o Put in order from least to greatest colligative properties. Then explain.
Ex 1: H2O (l) → H2O (l)
Ex 2: NaCl(s) → Na+(aq) + Cl- (aq) (2 moles of ions)
Ex 3: C6H12O6 (s) → C6H12O6 (aq) (1 mole)
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