Aqueous Solutions

Whether you use the term molarity, concentration or solubility they all represent the maximum amount of solute that can successfully be dissolved in a solvent. 

Solubility Rules

Concept: The Rules for the Solubility of a compound


Certain positive ions combine with negative ions to form either a liquid, aqueous, solid or gaseous compound. The Solubility Rules help us determine which form is created. 

Concept: The meaning of the terms soluble and aqueous


Saying a compound is soluble means that the compound will dissolve into aqueous ions in a solvent. These ions can conduct electricity and are called electrolytes

Concept: The meaning of the terms insoluble and precipitate


Saying a compound is insoluble means that the compound will not dissolve into aqueous ions and forms a solid called a precipitate, which will not conduct electricity. 


Whenever you add a solute to a solvent there are three possible outcomes: the solute dissolves completely, dissolves partially or doesn't dissolve at all into ions. 

Strong Electrolytes break up into ions completely and are broken down into 3 categories: Strong Acids, Strong Bases and Soluble Ionic Compounds

Weak Electrolytes partially break up into ions and are broken down into 2 categories: Weak Acids and Weak Bases

Non-Electrolytes do NOT break up into ions at all and are referred to as molecular compounds. 

Now that we have a more firm grasp on the types of electrolytes, we can now apply this knowledge to electrolyte based questions. 

Example: Each of the following reactions depicts a solute dissolving in water. Classify each solute as a strong electrolyte, a weak electrolyte or a non-electrolyte. 


Based on the different classifications of electrolytes we can expand to other compounds.

Problem: Classify each of the following solutes as either a strong electrolyte, a weak electrolyte or a non-electrolyte.


Writing Chemical Reactions

A balanced molecular equation is an equation showing the neutral forms of compounds. 

All that happens is that soluble ionic compounds separate and become ions in the chemical equationl. This represents the total or full ionic equation

In a balanced molecular equation reactant compounds exist as ions that recombine to form products. 

In a total ionic equation only the compounds that are aqueous can break up into ions. 

In a net ionic equation the spectator ions are removed and what remains is the net ionic equation

Remember when asked to write a complete and balanced molecular equation that a reaction only occurs if a solid, liquid or gas is formed as a product. 

Problem: Predict whether a reaction occurs, and write the balanced total and net ionic equations.


If your chemical equation produces only aqueous products then the answer is NO REACTION. 

Problem: Predict whether a reaction occurs, and write the balanced total and net ionic equations.