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  • Symbol:
  • Valency:
  • Atomic Number:
  • Atomic mass:
  • Electronic Configuration:
  • It lies in group along with . elements are collectively called Chalcogens (means ore forming).
  • It is known from ancient period as brimstone i.e. 'burning stone'.
  • It occurs free in nature in a volcanic area. In combined state, it is found as sulphides and sulphates of metal in the form of , etc.


  1. It is pale yellow.
  2. It is insoluble in water but dissolves in and .
  3. It’s molecular formula is .

Allotropes of Sulphur

A)Crystalline forms:

      1) Rhombic or :

- Most Stable form of Suphur.

- Shape of crystal = Octahedrol

- Molecular Formula =

- Shape of Molecule = Crown, chair and Boat

- Insoluble in water but soluble in .

-Bad conductor of heat and electricity.

-Pale yellow in colour but transparent.

-Melts at .Its density is .

2) Monoclinic Sulphur or Prismatic or :

-It is prepared by melting Rhombic Sulphur at followed by cooling.

-It is deep yellow crystalline solid but opaque.

-It is insoluble in Water but soluble in .

-Least Stable Form.

-Bad conductor of heat and electricity.

-Melts at .Its density is .

-It is stable above and below this changes into rhombic form. Hence, is the transition temperature.

B)Amorphous form:

1)Plastic or :

-It is prepared by plunging boiling sulphur into cold water.

-It is a supercooled liquid and does not have a sharp melting point.

-It consists of a long inverted zig-zag chain of sulphur atom.

-Insoluble in both and Water.

2) Colloidal sulphur of :

-It is prepared by oxidation of by oxidizing agents such as .

3)Milk of Sulphur:

-It is obtained by boiling sulphur and decomposing products formed with .

-It is white solid.

-It is used in medicine.


-Milk of sulphur is used in medicine.-Manufacturing of matches, gunpowder.-Used as disinfectant.-Vulcanization of rubber.

Compounds of


- Obtained by action of (non-oxidizing acids) on .

- It is purified by using MgO suspension in water.

- Moist is dried by using .

Chemical Properties:

1) Combustion

- With excess it gives .

- With Limited air it gives .

2) Acidic nature

- Weak and diprotic and dibasic acid.

3) Reducing action

-It reduces several oxidizing agent and gets oxidized to .

a) Halogen to haloacids.

b) to

c) Acidified to and pink colour decolourizes.

d) Acidified to and changes to green colour.

   e) to .

4) as analytical agent ( Used to detect metal ions)

a) It can precipate metal ions such as as Sulphide in acidic, basic and neutral medium.

b) It can precipate metal ions such as in basic medium of and .


-Bond angle :

-It is tested by using lead acetate .



 a) By burning Sulphur


b) By roasting of sulphide ore.


Lab preparation

-By action of on Copper.

Properties of

1)Acidic nature and is anhydride of .


2) Reducing action

It can reduce some oxidizing agents but self gets oxidized to .

3) Orange colour of acidified is converted to green.

4) It can reduce neutral to .

5) is oxidized by following (to )



    iii) .

6) It can reduce

   i) to

   ii) to

   iii) to

7)Halogen is reduced to haloacid

8) as oxidizing agent :



9)Bleaching action of is due to nascent Hydrogen .



-To manufacture .

-Used as bleaching agent for silk, wool, sugar solution.

-As germicide.



1) By dehydration of

2) By decomposition of and

3) By  Catalytic oxidation of .

Physical properties:

-It is colourless liquid and solidifies at .


Chemical Properties

 1) Acidic nature and anhydride of .

 2) Decomposition

3) Oxidizing action

4) With :


 (Sulphuric Acid or Oil of Vitriol or Chamber acid)

-It is manufactured by contact process. Steps involved are :

a) Production of

b) Catalytic oxidation of to

c) Conversion of to Oleum by adding .

d) Oleum is concerted to Sulphuric acid by adding calculated Water.

-In this manufacture , arsenic impurities is absorbed by .

Physical Properties

-It is syrupy liquid and corrosive nature.

-It is diluted by adding acid to water not water to acid.

 Chemical Properties

  1. Acidic nature and dibasic or diprotic acid.
  2. Decompose to give .
  3. It act as oxidizing agent as it produce nascent oxygen.
  4. Dehydrating agent:

a) Oxalic acid to and .

b) Formic acid to .

c) Alcohol to alkene

d) Carbohydrates to black mass of Carbon.


  • It is used in manufacture of dyes, detergents, explosives, fertilizers.
  • Used in lead acid Cell.


 1) By boiling solution of with Sulphur.

 2) By boiling and Sulphur.

Physical Properties

  • It is colourless crystalline solid soluble in water.


  • As a fixer in photography.
  • Used in estimated of iodine.