Solubility and Solubility Product

The dissolving of a sparingly soluble solute can be represented by an equilibrium equation:

As this is an equilibrium, we can write an equilibrium expression, called the Solubility Product:

The smaller the Solubility Product, the less soluble a solute is.

Solubility is usually expressed in one of two units: grams per litre (g L^-1); or moles per litre (mol L^-1).

We can use the solubility of a solute to calculate the Solubility Product, and use the the Solubility Product to calculate the solubility of a solute. Once we master these two skills, we have a good understanding of solubility.

Ionic Product and The Common Ion Effect

Ionic Product is the same as Solubility Product, but when two solutions (of known concentration) are combined and the ions may form a precipitate. If Ionic Product is larger than Solubility Product, a precipitate does form. If they are equal, it is a saturated solution. If Solubility Product is larger, no precipitate will form.

Aqueous Solutions Introduction - Species in Solution

This entire unit is about things dissolved in water - aqueous solutions. If they are not dissolved in water, we do not have to consider them (too much).

 The examples we need to work through by tomorrow are:

We also did a brief experiment to show why some salts are alkaliine or acidic:

Organic Chemistry Revision

We made hexagons to represent every functional group we studied in Organic Chemistry earlier in the year:

We are putting brief study notes on the back of these, and playing a few revision games with them:

Practical Electrochemistry

Today, we made some half-cells and combined them with a salt-bridge and a voltmeter. Then, we were asked to make sense of our observations.

Standard Electrode Potentials and EMF

This is a big idea and we will spend the rest of the week exploring it:

1. What are standard electrode potentials?
2. How are they used to find the EMF of a cell?
3. What happens if a cell has a negative EMF?
4. How can EMF be used to predict what would be observed in a redox reaction?
5. How can standard electrode potentials be used to rank oxidant- and reductant-strength?

Electrochemical Cells - Introduction

We started the lesson by making an electrochemical cell using zinc chloride, a zinc electrode, copper (II) sulfate, a copper electrode. We found that this generated about 1.4V