DISCOVERY OF BENZENE

1. Mr. Ansari Shoaib Ahmed

2. ROYAL SOCIETY OF CHEMISTRY
ROYAL SOCIETY Professional association in United kingdom
Purpose
“advancing the chemical sciences“
It was formed in 1980
Received a sample
Portable gas company in London this company was producing illuminating gas from
fish oil

3. • by product in a very large quantity
• sample was sent to the Royal Society to take ship for other applications if possible
• Sample landed in the Royal Society to Michael Faraday
Michael Faraday some basic chemical properties
• Specific gravity
• Solubility
• Reactions with acids
• Subjected to fractional distillation
As an assistant Humphry Davy
(1778-1829)

4. FRACTIONAL DISTILLATION
• fractional distillation is a technique to separate mixture of liquids having different
boiling points
• for example crude oil
• crude oil is a mixture of different hydrocarbons and other organic components
• fractional distillation is performed daily in petroleum industry to separate
petrochemicals
• if the mixture of organic compound is known exactly temperature can be set
• if the mixture of organic compound is unknown a qualitative experiment can be
performed.
?

6. • Faraday's separated the fractions by the difference of 10 degrees Fahrenheit (10oF)
• Mixture was separated between 176 degree to 190 degree Fahrenheit
• He named the compound as the bicarburate of the hydrogen(C2H) and continued his
studies.
• It was largest part of oil while other parts their not found significant or they were
inactive
PROPERTIES FARADAY REPORT PRESENT VALUE
Specific Gravity Nearly 0.85 at 15.5oC 0.885 at 15oC
Melting point 5.5oC (42oF) 5.483oC
Boiling point 85.5oC (186oF) 80.4oC
Vapour Density Nearly 40 39.024

7. • Eilhard Mitscherlich (1834)
• Prepared the same substance in 1930 by reacting with benzoic acid from
gum benzoin
• Relative molecular mass was 78
• Molecular weight CH
• Gave name Benzene

8. • August Kekule’ in 1865
• Molecular formula C6H6
• He was studying architecture first but letter change to chemistry
• He had very good ability of imagination
• One night he sat down to write his book and feeling to sleep
• Dreamed a snake biting his own tail
• All of a sudden woke up and cracked the structure of benzene