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.