Alkanes
Chapter Name : Hydrocarbons |
Sub Topic Code : 102_11_13_02_01 |
Topic Name : Alkanes |
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Sub Topic Name : Alkanes |
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Introduction
Hydrocarbons which contain only single bonds are called alkanes. They are called saturated hydrocarbons because there is hydrogen in every possible location. This gives them a general formula CnH2n+2.
Pre-Requisites:
Alkanes
Activity:
Kerosene.
Real Life Question:
What are alkanes?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Alkanes | Hydrocarbons which contain only single bonds are called alkanes. They are called saturated hydrocarbons because there is hydrogen in every possible location. This gives them a general formula CnH2n+2. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Gasoline | A mixture of alkanes from pentane up to about decane. |
Real life uses :
Used mainly for heating and cooking purposes.
Places to visit :
Chemistry laboratory.
Practical examples around us
| Examples | Explainations |
|---|---|
| methyl | A methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms — CH3. |
What you learn in Theory:
Alkanes react with halogens in a so-called free radical halogenation reaction. The hydrogen atoms of the alkane are progressively replaced by halogen atoms. Free-radicals are the reactive species that participate in the reaction, which usually leads to a mixture of products. The reaction is highly exothermic, and can lead to an explosion.
What you learn in Practice:
Alkanes are only weakly reactive with ionic and other polar substances. The acid dissociation constant (pKa) values of all alkanes are above 60; hence they are practically inert to acids and bases.