Why are alkenes and alkynes called unsaturated compounds?

1 Answer
Mar 16, 2015

Answer:

Alkenes and alkynes are called unsaturated compounds because the carbon atoms that they contain are bonded to fewer hydrogen atoms than they can possibly hold.

Explanation:

Alkenes and alkynes are called unsaturated compounds because the carbon atoms do not have as many hydrogen atoms as they possibly could.

A saturated compound contains a chain of carbon atoms joined by single bonds, with hydrogen atoms filling all of the other bonding orbitals of the carbon atoms.

An example is butane, CH₃-CH₂-CH₂-CH₃.

It is saturated because every carbon holds as many hydrogen atoms as possible.

Alkenes such as but-2-ene (CH₃-CH=CH-CH₃) and alkynes such as but-2-yne, (CH₃-C≡C-CH₃) are unsaturated because the middle carbons contain fewer hydrogen atoms than they possibly could.