1. General Introduction

CHAPTER- 12 ORGANIC CHEMISTRY – SOME BASIC PRINCIPLES AND TECHNIQUES

GENERAL INTRODUCTION

Organic chemistry is the branch of chemistry that deals with carbon compounds. But all carbon compounds are not considered as organic compounds. (E.g. CO₂, CO, metal carbonates, bicarbonates etc.). So organic chemistry can be defined as the branch of chemistry that deals with hydrocarbons and their derivatives. Hydrocarbons are the major class of organic compounds and they contain only carbon and hydrogen atoms. All other organic compounds are formed by replacing one or more hydrogen atoms of hydrocarbons by other atoms or groups (They are called hydrocarbon derivatives).

All carbon compounds present in plants and animals are organic compounds. E.g. Carbohydrates, proteins, vitamins, nucleic acids, amino acids, fats and oils, natural polymers etc. petroleum and coal are the major source of organic compounds (hydrocarbons).

In ancient times, it was believed that a vital force (living body) is necessary for the production of an organic compound. But in 1828, Frederic Wohler proved that this belief was wrong. He prepared urea in the laboratory, by heating ammonium cyanate (NH₄CNO). It was the first organic compound prepared in the laboratory.

NH₄CNO ⎯⎯ Heat⎯→ NH₂CONH₂ 

Then another scientist Kolbe synthesized acetic acid and Berthelot synthesized methane in the laboratory. Nowadays about 95% of the organic compounds are synthesized in the laboratory.