Which of the Following is True of the IUPAC System

Question

Which of the following is true of the IUPAC system of naming alkenes?
A) The alkene is named based on the longest carbon chain that contains the double bond.
B) The position of the double bond is always given the highest possible number.
C) The position and identity of substituents determine the number associated with the position of the double bond.
D) None of these are correct.

Accepted Answer

In the IUPAC system, the alkene is named based on the longest carbon chain that contains the double bond. The position of the double bond is then indicated by the lowest number possible. If there are substituents, the carbon atoms in the main chain are numbered in such a way that the substituents receive the lowest possible numbers.