Question

Name the compound.
${\text{C}}{{\text{H}}_{\text{3}}}{\text{ - CH = CH - C}}{{\text{H}}_{\text{3}}}$

Answer 1

For the nomenclature of any compound first, we should know about the rules given by the IUPAC which stands for International Union of Pure And Applied Chemistry.

Complete Solution :
According to the rules of IUPAC, we will give the name to this ${\text{C}}{{\text{H}}_{\text{3}}}{\text{ - CH = CH - C}}{{\text{H}}_{\text{3}}}$ compound by following manner:
-First we count the no. of carbon atoms in the given compound and there are four carbon atoms present in the given compound, so we use –But as a prefix.
-Now we observe which number of carbon atom double bonds is present and we should provide low numbering to that carbon atom. And a given compound double bond is present in the 2nd carbon atom.
-As we know that whenever in any compound if double bond is given then that compound will come under the category of alkenes.
So, the name of ${\text{C}}{{\text{H}}_{\text{3}}}{\text{ - CH = CH - C}}{{\text{H}}_{\text{3}}}$ compound is But-2-ene.

Additional information: But-2-ene is mainly used for the production of gasoline or petrol. Its appearance is colorless and it is also known as colorless compressed liquefied gas or petroleum gas. Due to the presence of double bond and two different groups on the double bonded carbon atoms, it shows geometrical isomerism or in other words cis-trans isomerism.

Note: During the nomenclature of above compound if you do not write 2 & only write butene then that will be wrong, because in butene double bond is present in the 1st carbon atom. So, you have to write But-2-ene.