Genetics

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Chapter 13
The Properties of Mixtures: Solutions and Colloids
Last chapter we talked about pure substances ¡V liquids and solids. This chapter deals with mixtures, specifically homogeneous mixtures called solutions. A solution is composed of two parts called components:
1. solvent ¡V substance present in larger amount
2. solute ¡V substance being dissolved
Other terms you will want to remember:

heterogeneous mixture
soluble
insoluble
solubility
solubility limit
dynamic equilibrium vs static equilibrium
„^
(From last chapter)
A solution occurs when two substances are uniformly mixed. A lot of properties of solutions once again depend upon the intermolecular forces present in the solution. In pure liquids, there is only one component and thus, the interaction between particles is the same. In a solution, the solute particles differ from the solvent particles and thus, we have different types of interaction. There are interactions between solute particles, between solvent particles and between solute and solvent particles. The relative strengths and types of the intermolecular forces between the components determines solubility of one substance in another.
Let¡¦s look at NaCl dissolving in water. As we have discussed before, NaCl is dissolved by water since the attractive force is stronger between the particles of water and the ions than is the attractive force between the ions themselves

Called solvation (when solvent is H2O ƒ­> called hydration)
The ion ¡V dipole force is greater than the hydrogen bonding between the water molecules and also greater than the ionic bond in NaCl (one reason being that there is often more than one water molecule associated with the ion).
Identify the: solute „_ NaCl
solvent „_ H2O
solution „_ NaCl & H2O combined

The three attractive interactions are:
1. solute ¡V solute interactions
2. solvent ¡V solvent interactions
3. solute ¡...