Table of Contents
ToggleLaboratory Preparation of methane/alkane, its principle, procedure, and uses in organic chemistry have been discussed here:
General Methods of Preparation of Alkanes
Some of the important methods of preparation of alkanes in the laboratory are discussed below:
From alkyl halides
Alkanes can be prepared from alkyl halides by the following two methods:
Wurtz reaction
When alkyl halide is treated with sodium in dry ether, symmetrical alkane (for the same alkyl halide) or a mixture of products (different alkyl halide) is obtained.
Reduction of alkyl halides
Alkyl halides on reduction with suitable reducing agents get converted into alkane.
From carboxylic acids
Alkanes can be prepared from carboxylic acids by the following methods:
Decarboxylation reaction
When sodium salt of monocarboxylic acid is heated with soda lime, alkane is obtained with the removal of a CO2 molecule, and hence is a decarboxylation reaction.
Reduction of carboxylic acids
When carboxylic acids are reduced with hydriodic acid in the presence of red phosphorus, alkanes are produced.
From Grignard reagent
From unsaturated hydrocarbons
By catalytic hydrogenation, unsaturated hydrocarbons can be converted into alkanes.
Laboratory preparation of methane
Following method is one of the major laboratory methods of manufacturing methane in the laboratory.
Principle involved in laboratory preparation of methane
Methane gas can be made in the laboratory by heating a mixture (1:4 ratio) of anhydrous sodium acetate and soda-lime. Here, CaO is employed as a dehydrating agent, NaOH is a deliquiscent solid, and the reaction involves decarboxylation.
Procedure for the preparation of methane
A copper tube is filled with a 1:4 combination of anhydrous sodium acetate and soda-lime. A cork and delivery tube are attached to a copper tube. The delivery tube’s second end is inserted into the beehive shelf, which is placed underwater.
On heating, methane gas is evolved which can be collected by the downward displacement of water.
Lab Preparation of methane video
Uses of methane
- Used as a fuel
- Used to provide lighting
- Used in the production of methanol, hydrochloric acid, hydrogen, and so on.
- Used as a fertilizer ingredient
References
- Morrison, R. T., & Boyd, R. N., Organic chemistry, Allyn and Bacon, Inc. 1987.
- March, J., Advanced Organic Chemistry, Wiley Eastern Limited, 1986.
- Bahl, B.S., A., Advanced Organic Chemistry, S. Chand and Company Ltd, New Delhi, 1992.
- Finar, I. L., Organic Chemistry, Vol. I and Vol. II, Prentice-Hall, London, 1995.