Category: Chemistry

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Method of Preparation of Alcohols

There are various methods of preparation of alcohols. Here are discussed many ways to prepare alcohols. (1) From Haloalkanes (2) By Reduction of Aldehydes and ketones (3) By Reduction of Carboxylic acid and esters ** Tertiary alcohols cannot be obtained by reduction of Acids or esters (4) From Grignard Reagent – Formaldehyde gives primary alcohol […]

Why Apples Turn Brown on Exposure to Air

Eating an apple daily keeps a doctor away’ we have heard this so many times from our parents. But do you know why an apple turns Brown when it is exposed open to air? Here is the answer Apple contain an enzyme called polyphenol oxidase (PPO) also known as tyrosinase. Cutting an apple exposes its […]

Calculation of oxidation Number in Redox Reactions

Oxidation number of the element is defined as the residual charge which its atom has when all other atoms from the molecule are assumed to be removed as ions. General oxidation number of different groups are as follows: IA +1 IIA +2 IIIA +3/ +1 IV A – 4 to +4 V A – 3 […]

Preparation of Amines

1. Reduction of Nitro Compounds By passing H2 gas in presence of finely divided Ni, Pd, or Pt     By reduction with metals in acidic medium   2. Ammonolysis of Alkyl Halides The carbon−halogen (C−X) bond in alkyl or benzyl halides can be easily cleaved by a nucleophile. The process of cleavage of C−X […]