Is Matter around us pure
Introduction
When we talk about pure, it means that all the constituent particles of that substance are the same in their chemical nature. A pure substance consists of a single type of a particles. What is the type of pure substances?
- Elements
- Robert Boyle A was the first scientist to use the term element in 1661.
- Antoine Laurent Lavoisier (1743–94), a French chemist, was the first to establish an experimentally useful definition of an element.
- Elements can be normally divided into metals, non – metals and metalloids.
Metals
- Metals usually show some or all of the following properties:
- They have a lustre (shine).
- They conduct heat and electricity.
- They are ductile (can be drawn into wires).
- They are malleable (can be hammered into thin sheets).
- They are sonorous (make a ringing sound when hit).
# Examples of metals are gold, silver, copper, iron, sodium, potassium etc.
# Mercury is the only metal that is liquid at room temperature.
Non metals
- Non – metals usually show some or all of the following properties:
- They are poor conductors of heat and electricity.
- They are not lustrous, sonorous or malleable.
# Examples of non – metals are hydrogen. oxygen, iodine, carbon (coal, coke). bromine, chlorine etc.
Metalloids
- Metallaoids have intermediate properties between of metals and non – metals.
# Examples are boron, silicon, germanium etc.
Mixture and compound
Mixture | Compound |
1. Elements or compounds are simple calling so new substance is formed. Compound | 1. Substances Are Reated Together with each other to make a new substance. |
2. Elements do not combine in a fixed ratio. | 2. Compositions the the component is Fixed i.e. , They combine together in a fixed ratio according to their masses. |
3. A mixture shows the properties of its components | 3. compound does not show the Properties of component elements. |
4. Components can be easily separated by any mechanical method which is suitable. | 4. components can not be separated from each other by simple mechanical methods. |