Chapter 1: Matter and Measurement

General Chemistry
Principles and Modern Applications
Petrucci • Harwood • Herring
8th Edition

Chapter 14: Solutions and Their
Physical Properties
Philip Dutton
University of Windsor, Canada
N9B 3P4
Prentice-Hall © 2002


Contents
14-1
14-2
14-3
14-4
14-5
14-6
14-7

Types of Solutions: Some Terminology
Solution Concentration
Intermolecular Forces and the Solution Process
Solution Formation and Equilibrium
Solubilities of Gases
Vapor Pressure of Solutions
Osmotic Pressure

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Contents
14-8

Freezing-Point Depression and Boiling-Point Elevation
of Nonelectrolyte solutions.
14-9 Solutions of Electrolytes
14-10 Colloidal Mixtures
Focus on Chromatography

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13-1 Types of Solution:
Some Terminology
• Solutions are homogeneous mixtures.
– Uniform throughout.

• Solvent.
– Determines the state of matter in which the solution
exists.

– Is the largest component.

• Solute.
– Other solution components said to be dissolved in the
solution.
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Table 14.1 Some Common Solutions

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14-2 Solution Concentration.
• Mass percent.
• Volume percent.
• Mass/volume percent.

(m/m)
(v/v)
(m/v)

• Isotonic saline is prepared by dissolving 0.9 g
of NaCl in 100 mL of water and is said to be:
0.9% NaCl (mass/volume)

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10% Ethanol Solution (v/v)

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ppm, ppb and ppt
• Very low solute concentrations are expressed as:

ppm: parts per million
ppb: parts per billion
ppt: parts per trillion

(µg/g, mg/L)
(ng/g, µg/L)
(pg/g, ng/L)

note that 1.0 L  1.0 g/mL = 1000 g
ppm, ppb, and ppt are properly m/m or v/v.
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Mole Fraction and Mole Percent

χ=

Amount of component i (in moles)
Total amount of all components (in moles)

χ1 + χ2 + χ3 + …χn = 1
Mole % i = χi  100%

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Molarity and Molality

Molarity (M) =

Molality (m) =

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Amount of solute (in moles)
Volume of solution (in liters)

Amount of solute (in moles)
Mass of solvent (in kilograms)

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14-3 Intermolecular Forces and the
Solution Process

ΔHc

ΔHb

ΔHa

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Intermolecular Forces in Mixtures
• Magnitude of ΔHa, ΔHb, and
ΔHc depend on intermolecular
forces.
• Ideal solution
– Forces are similar between all
combinations of components.

ΔHsoln = 0

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Ideal Solution

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Non-ideal Solutions
• Adhesive forces greater

than cohesive forces.

ΔHsoln < 0
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Non-ideal Solutions
• Adhesive forces are less than
cohesive forces.
ΔHsoln > 0

• At the limit these solutions
are heterogeneous.
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Ionic Solutions

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Hydration Energy
NaCl(s) → Na+(g) + Cl-(g)

ΔHlattice > 0

Na+(g) + xs H2O(l) → Na+(aq)

ΔHhydration < 0

Cl-(g) + xs H2O(l) → Cl-(aq)

ΔHhydration < 0

ΔHsoln > 0 but ΔGsolution < 0

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14-4 Solution Formation and Equilibrium

saturated

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Solubility Curves
Supersaturated

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Unsaturated

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14-5 Solubility of Gases
• Most gases are less soluble
in water as temperature
increases.
• In organic solvents the
reverse is often true.

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