• 3 credits internally assessed.• Practical component with written

answers.

This topic covers: Qualitative – definitions of solubilitySolubility rulesIdentifying ionsBalancing ionic equationsComplex ions Balancing complex ion equations

AS 91162 Carry out procedures to identify ions present in solution

Made up of +ve and -ve ions

+ve -ve

Cation Anion

Held together by the electrostatic attraction between the +ve and -ve charges.

Overall ionic compounds are neutral.

What are ions?

A liquid mixture of solute (solid) dissolved in solvent (liquid).

Note: Most of the H+ and OH- combine to form H2O.

What’s a solution?

Question: How do we know what ions are present in a solution?

So what’s the ‘solution’ to this problem?

1. Taste the chemicals?2. See the chemicals?3. Feel the chemicals?4. Try putting other chemicals to

see if it reacts?5. Or just ask whoever made the

chemicals?

This type of experiment is called Qualitative analysis which is about finding out what is there.

Qualitative – an analysis using qualities such as colour change, smell or precipitation (cloudiness)

Quantitative – an analysis using quantities like volume, mass or amount

Quality not quantity.

It turns out that many ions are colored (especially the metal ones) and is easily identifiable, now lets observe some chemicals and note down the color of them.

Practical