Ch 15/16
81. Factors that affect solubility
Temperature- the solubility of most solid substances increases as the temperature pf the
solvent increases.
Pressure- changes in pressure have little affect on the solubility of solids and liquids, but
pressure strongly influences the solubility of gases.
Temperature affects the solubility of solid, liquid, and gaseous solutes in a solvent; both
temperature and pressure affect the solubility of gaseous solutes.
82. Solution- a homogeneous mixture, consist of solutes dissolved in a solvent.
83. Solute vs. Solvent
Solvent - dissolving medium
Solute - dissolving particles
A solvent dissolves the solute. The solute becomes dispersed in the solvent.
85. Rates of dissolution
86. Electrolytes
A compound that conducts an electric current when it is in an aqueous solution or in the
molten state.
All ionic compounds are electrolytes because they dissociate into ions.
nonelectrolytes- a compound that does not conduct an electric current in either aqueous
solution or the molten state.
Strong electrolytes- a solution in which a large portion of the solute exist as ions.
Weak electrolytes- a solution that conducts electricity poorly because only a fraction of
the solute exists as ions.
87. Saturated vs. unsaturated vs. dilute vs. supersaturated
Saturated solution- contains the maximum amount of solute for a given quantity of
solvent at a constant temperature and pressure.
Unsaturated solution- a solution that contains less solute than a saturated solution at a
given temperature and pressure.
Supersaturated solution- contains more solute than it can theoretically hold at a given
temperature.
Dilute solution- is one that contains a small amount of solute.
89. Miscible- liquids that dissolve in each other in all proportions.
Immiscible- liquids that are insoluble in one another.
91. Concentration- is a measurement of the amount of solute that is dissolved in a given
quantity of solvent, usually expressed as mol/L.
92. Molarity- the number of moles of solute dissolved in one liter of solution.
moles of solute
M= --------------------Liters of solution
93. What is the molarity of a solution containing 9.0 moles of solute in 2.500 L of
solution?
Given: 9.0 mol
Find: M Use: M= mol/L
9.0/2.5 = 3.6 M
2.500 L
More practice problems:
1. How many grams of NaCl are present in 2 liters of a 0.05M brine solution?
Given: 2L
Find: g / NaCl
0.05M
molar mass: 58.5gNaCl
0.1 mol NaCl
----------------1
58.5gNaCl
 ---------------- = 5.8g NaCl
1mol Nacl
2. How many liters of 0.30 M solution are needed to give 2.7 moles of solute?
3.how many grams of NaCl would be required to produce a 3.0M solution with a volume
of 500mL?
96. Changing concentration problem:
1. If 1.0mL of 6.0M HCI is added to 499mL of water to give exactly a 500 mL solution,
What is the molarity of the dilute solution?
Given: 1.0 mL of 6.0M, 500mL Use: Mi Vi=Mf Vf
Find:M
(1.0mL)(6.0M)
--------------------- = .012M
500mL