Dear Readers welcome to Awareness Adda. Today article is Chemistry, it was also an important topic in SSC and RRB examinations, and Chemistry is one of the large subjects. But we can provide you important materials which helped to you get a good score in your examination. so keep in touch with us, today article contains Introduction to Chemistry. so friends let’s start to knowing about Chemistry.

Physical Chemistry:

            It also depends on the matter it was mainly divided into two types they are given below.

  1. Physical compositions.
  2. Chemical compositions.

Physical composition: –

It is mainly divided into 3 groups they are given below,

  1. Solid State.
  2. Liquid State.
  3. Gases State.

Solid State:

  • It has a definite shape.
  • Solids are stiff.
  • Solids are practically incompressible.
  • Solids have a definite volume.
  • Diffusion of solids is extremely slow.

Liquids State:

  • They do not a definite shape.
  • Liquids molecules are closely packed.
  • Liquids molecules have appreciable cohesive forces.
  • Liquids have a definite volume.
  • Liquids are diffusing but rather slowly.

Gases State:

  • Gas molecules do not have definite shape
  • Gas molecules are simplicity and un-uniformity
  • Gas molecules are compressible
  • Gases have not definite volume
  • Gases the diffusion of gases is very fast.

Note:             water exists in three different states, ice is a solid state when we heat it becomes water it is liquid state still we heats the water then it becomes vapour which is gases state.

            The three states of matter are solid liquid and gaseous state. The fourth state of matter plasma state and fifth state of matter Bose-Einstein Condensation state.

Plasma state:

  • Plasma state consists of super energetic and super excited particles.
  • These particles are in the form of ionised gases.
  • Plasma can occur when the matter is heated to very high temperature.
  • The matter in a plasma state is a collection of free highly energetic and highly excited electrically charged particles.

Bose-Einstein Condensation state:

  • On the basis of statistical calculations, Satyendra Nath Bose gave the concept of the fifth state of matter.
  • This state is formed by supercooling a gas of extremely low density, about one hundred-thousandths of the density of normal air, to super low temperature.

Chemical Compositions:

            In here chemical classifications is divided into two groups.

  1. Pure substances.
  2. Mixture.

Pure substances:

            A single substance or a matter which cannot be separated into another kind of matter by any physical process is called pure substances.

A pure substance is classified into two categories.


Elements are classified into three types.

  • Metals.
  • Nonmetals.
  • Metalloids.


  • Metals are solids and normally hard.
  • They have lustre, high melting point and boiling point.
  • It is also a good conductor of electricity and heat.
  • The conductivity of metals decreases with increasing of temperature vibration of positive ions at their lattice points.
  • Iron, copper, silver, gold are the examples.


    • Nonmetals are the elements with opposite properties to those of the metals.
    • They are found in all states of the meter.
    • They are poor conductors of electricity.
    • Hydrogen, carbon, oxygen, nitrogen. Etc.


  • Metalloids are the elements which have common properties of both metals and nonmetals.
  • Arsenic, antimony, bismuth are the examples.


Compounds are pure substances that are composed of two or more different elements in a fixed proportion by mass.

Note: the properties of compounds are entirely different from those of the elements from which it is made. Example: water, sugar, alcohol etc.

In here compounds are classified into two groups. Those are given below.

  • Organic compounds.
  • Inorganic compounds.

Organic compounds:

This compounds obtained from living sources are called organic compounds. Carbohydrates, proteins, oils, fats etc.

Inorganic compounds:

These compounds obtained from non-living sources such as rocks and minerals are called Inorganic compounds. Salt, washing soda, marble etc. are the examples.


Mixtures is a material obtained by mixing two or more substances in any indefinite proportion is called a mixture.

The properties of the components in a mixture remain unchanged. Sea water, petrol, paint, cement etc are the examples.

Mixtures are classified into two groups.

  • Homogeneous mixture.
  • Heterogeneous mixture.

Homogeneous mixture:

A mixture is said to be homogeneous if it has a uniform composition throughout, there are no visible boundaries of separation between constituents.

Examples: common salt dissolved in water, sugar dissolved in water.

Heterogeneous mixture:

A mixture is said to be heterogeneous if it does not have a uniform composition throughout. There are visible boundaries of separation between the various constituents.

Examples:  a mixture of sulphur & sand, a mixture of iron fillings & sand etc..

Separation of mixtures:

                There are some methods are used to separation of mixtures those are given below.

  1. Sublimation: it is a process of conversion of a solid into a vapour without passing through the liquid state. Ex: naphthalene, iodine, ammonium.
  2. Filtration: in this process is the quick and complete removal of suspended solid particles from a liquid, ex: removed of solid particles from the engine oil in a car engine.
  • Evaporation: the process of conversion of a liquid into its vapours at room temperature is called evaporation. Ex: evaporation of water in summer from ponds, wells and lakes.
  1. Crystallisations: In this process, the impure solid or mixture is heated with suitable solved to its boiling point and the hot solution is filtered.
  2. Distillation: it is a process of converting a liquid into its vapour by healing and then condensing the vapour again into the same liquid by cooling.

Distillation=Vaporization + Condensation.

  1. Fractional distillation: The process is similar to the distillation process. Except that fractionating column is used to separate two or more volatile liquid which has different boiling points.
  • Chromatography: the name chromatography is derived from Latin word ‘Chroma’ meaning colour. The technique of chromatography is based on the difference in the rates at which the components of a mixture are absorbed in the suitable absorbent.
  • Sedimentation and Decantation: this method is used when one component is a liquid and other is insoluble. Insoluble solid, heavier than liquid. I.e. mud and water.

            All these are the physical and chemical compositions detailed explanation, in next article, we will provide you more material on the next topic. So keep in touch with Awareness Adda. Always remember that “There are no secrets to success. It is the result of preparation, hard work, and learning from failure”. All The Best and Thank you.