1. 8.2 Solutions and Their Characteristics 8.3 The Dissolving Process
Chapter 8 Solutions
8.2 Solutions and Their Characteristics
8.3 The Dissolving Process

2. Solution: a homogeneous (one phase) mixture that contains at least one solute and one solvent
- the solute is the substance that is dissolved in a solvent
- the solvent is the liquid substance in which the solute is dissolved
there are different types of solvents but the most common is water which is called an aqueous solution
There are heterogeneous mixtures. Oil and water is a classic example of this. Two different phases are visible.

3. Concentration: the ratio of the quantity of solute to the quantity of solution (solvent)
Concentrated solutions have high ratios
Dilute solutions have low ratios

4. Different types of solutions

5. Properties of Aqueous Solutions
can be subdivided at electrolytes or nonelectrolytes
- electrolytes are generally high soluble ionic compound that conduct electricity
or by pH (acid, base, neutral)
Scale goes from 0-14, where 7 is neutral
Below 7 acidic
Above 7 basic

6. 8.3 The Dissolving Process
we can explain some physical properties using intermolecular (between molecules) and intramolecular (between atoms in a molecule) forces
water is a polar molecule that is capable of hydrogen bonding
thus any polar substances should easily dissolve in water
any molecule containing N, O or F has a high probability of forming hydrogen bonds

7. Ionic compounds tend to dissociate in water
This allows them to conduct electricity

8. Dissociation Equations
Show how ionic compounds dissolve in water

9. Dissociation Equations
Complete dissociation equations for 1- barium sulfate, 2- iron (II) phosphate

10. Dissolving of Molecular Compounds
Molecular compounds vary in their ability to dissolve
Molecular substances typically experience London forces between molecules
This keeps them from dissociating
They tend to be molecules that do not contain O, N, or F because these are capable of hydrogen bonding and will mix with water to some extent
Those that consist of mainly carbon and hydrogen tend not to dissolve

12. “Like dissolves Like”
Ionic compounds and polar covalent compounds dissolve in polar solvents as a result of solute-solvent attractions
A non-polar solute will generally dissolve in a non polar solvent

13. Surfactants
Oil and water can mix together in the presence of a surfactant
A surfactant is a substance that acts on the surface of a liquid and reduces surface tension
The surfactant works to break hydrogen bonds at the surface that keep water and oil separated

14. Micelles
Detergents and soaps form Micelles which are able to trap grease and remove it from an object