Alkynes
Chapter Name : Hydrocarbons |
Sub Topic Code : 102_11_13_04_05 |
Topic Name : Alkynes |
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Sub Topic Name : Physical Properties |
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Introduction
In organic chemistry, an alkyne is an unsaturated hydrocarbon which has at least one carbon-carbon triple bond between two carbon atoms. The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula CnH2n-2.
Pre-Requisites:
Alkynes
Activity:
Graphite.
Real Life Question:
What are alkynes?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Alkynes | Alkynes are generally nonpolar molecules with little solubility in polar solvents, such as water. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| triple bond | A chemical bond between two chemical elements involving six bonding electrons instead of the usual two in a covalent single bond. The most common triple bond that between two carbon atoms can be found in alkynes. |
Real life uses :
Alkanes are our fuels. From the gases, methane, to butane, The liquid fuel for cars, in theory about C8 alkanes, Kerosene for heating and aircraft, All the way up to heavy fuel oils.
Places to visit :
Chemistry laboratory.
Practical examples around us
| Examples | Explainations |
|---|---|
| ethyne | The chemical compound with the formula C2H2. It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in pure form and thus is usually handled as a solution. Pure acetylene is odorless, but commercial grades usually have a marked odor due to impurities. |
What you learn in Theory:
Alkynes have physical properties similar to alkanes and alkenes. Lower alkynes up to four carbon atoms are gases, those containing five to thirteen carbon atoms are liquids while higher alkynes are solids.
What you learn in Practice:
Alkynes are generally nonpolar molecules with little solubility in polar solvents, such as water. Solubility in nonpolar solvents, such as ether and acetone, is extensive. Like the alkanes and alkenes, alkynes of four or fewer carbon atoms tend to be gases.