Alkynes have pretty much the same physical properties as those of alkanes and alkenes.

• Non-polar hydrocarbons
• Insoluble in water
• Soluble in non-polar solutions
• Less dense than water
• Their boiling points usually increase with increasing carbon number

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Chemical Properties:

These are some of the chemical properties of common alkynes:

• Combustion: Alkynes burn in air with a luminous, smoky flame, (forming carbon dioxide and water)
• Dangerously explosive when mixed with air or oxygen
• Substitution reaction: The reactions of ethynes (a type of alkyne) indicate acidic properties for the hydrogens, which are attached to the carbon atoms involved in the triple bond
• Ethynes readily form compounds with metals

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