1.2 Basic Definitions

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chemistreepk.blogspot.com

Basic Definitions

Matter

Anything around us which has some mass and occupies some space is known as Matter.
For example, Everything around us in this world is an example of matter.

Types

There are three types of matter:

  • Solid
  • Liquid
  • Gasses

Substance

"A piece of matter which is in pure form is known as substance."

Elements

The sum of atoms having the same atomic number and it can not be broken down into simpler atoms by chemical or physical means is known as Elements.
Example: All elements of the periodic table are examples of it such that; Oxygen(O2), Hydrogen(H2) and Nitrogen(N2), etc.

Compounds

Any substance which is an identical molecule and consists of the sum of atoms of two or more types of elements is known as a Compound.
Example: CO2, H2O, and H2SO4 are an example of compounds.

Mixtures

"A piece of matter which is in impure form is known as a mixture."
The combination of two or more chemical elements which are combined physically to each other and not chemically is known as a Mixture.
Example: Air, soil, and petroleum products are examples of mixtures.

Homogenous Mixtures

"That type of mixtures in which the composition of its components is uniform is known as homogenous mixtures."
Example: Air, gasoline and ice cream, etc.

Heterogeneous Mixtures

"That type of mixtures in which the composition of its components is not uniform are known as heterogeneous mixtures."
Example: Soil, rock, and wood, etc.

Properties of Matters

Matters have two types of properties:

Physical Properties

"That type of properties which are concerned with the physical state of a substance is known as physical properties."
Example: Color, smell, taste, hardness of shape of the crystal, solubility and melting or boiling points, etc.

Chemical Properties

"That type of properties which are concerned with the chemical state of a substance is known as chemical properties."
When any substance undergoes a change in its chemical composition its composition is changed and a new substance is formed.
Example: Decomposition of water is an example of a change in chemical properties because new components such as hydrogen(H) and oxygen(O) are formed.

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Location Lahore, Punjab, Pakistan
Hello, this is Misbah ud Din a student of STEM. This is my blog chemisTREEpk which provides a vast knowledge about Chemistry(and sometimes other sciences) fully free.

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