Is Matter Around Us Pure?
1. Introduction
In daily life, the word pure means clean or free from contamination. But in science, a substance is called pure only if it contains one type of particle throughout. For example, distilled water is scientifically pure, but normal water is a mixture of salts and gases.
2. Types of Matter Based on Purity
| Type | Description | Examples |
|---|---|---|
| Pure Substance | Only one type of particle | Gold, Distilled water |
| Mixture | Two or more substances mixed physically | Air, Saltwater, Milk |
3. Pure Substances (Element & Compound)
| Type | Definition | Example |
|---|---|---|
| Element | Made of single type of atom | Iron, Gold, Oxygen |
| Compound | Chemically combined in fixed ratio | NaCl, H2O |
4. Mixtures
| Type | Feature | Example |
|---|---|---|
| Homogeneous | Uniform mixture | Air, Sugar solution |
| Heterogeneous | Non-uniform mixture | Oil and water, Soil |
5. Solution – Solute, Solvent
| Term | Definition | Example |
|---|---|---|
| Solute | Substance that dissolves | Sugar |
| Solvent | Substance that dissolves solute | Water |
| Solution | Homogeneous mixture of solute + solvent | Sugar in water |
Formula – Concentration
Mass by Mass % = (Mass of solute / Mass of solution) × 100
Mass by Volume % = (Mass of solute / Volume of solution) × 100
Volume by Volume % = (Volume of solute / Volume of solution) × 100
Mass by Volume % = (Mass of solute / Volume of solution) × 100
Volume by Volume % = (Volume of solute / Volume of solution) × 100
6. Colloid & Suspension Comparison
| Property | Solution | Colloid | Suspension |
|---|---|---|---|
| Particle Size | < 1 nm | 1–100 nm | > 100 nm |
| Settling | No | No | Yes |
| Tyndall Effect | No | Yes | Yes |
| Example | Sugar water | Milk | Muddy water |
7. Separation Techniques
| Method | Used For | Example |
|---|---|---|
| Filtration | Insoluble solid from liquid | Sand + Water |
| Evaporation | Soluble solid + liquid | Salt from seawater |
| Distillation | Liquids with different boiling points | Alcohol + Water |
| Chromatography | Color separation | Ink components |
🧠DHved One Page Summary Hack
Pure = Single Particle | Mix = Physical blend | Solution = Clear | Colloid = Tyndall | Suspension = Settles | Separation Code → F E C S C D F
🎯 Practice Sheet with Interactive Quiz
MCQ Test – Click to Check Answers
1. Which of the following is a heterogeneous mixture?
AirBrass
Oil and water
Sugar solution
2. Tyndall effect is shown by:
True solutionColloid
Suspension
Compound
3. Distillation is used to separate:
Alcohol and waterMud and water
Cream and milk
Sand and salt