Which of the following compounds have the same degree of unsaturation?

Question

Quizplus · Accepted Answer

Degree of unsaturation (DU) = (2n+2-H-X)/2 where n is the number of carbons, H is the number of hydrogens, and X is the number of halogens.

For compound I: 
n=7, H=10, X=0 
DU = (2(7)+2-10-0)/2 = 4

For compound II: 
n=8, H=10, X=0 
DU = (2(8)+2-10-0)/2 = 5

For compound III: 
n=8, H=9, X=0 
DU = (2(8)+2-9-0)/2 = 4

For compound IV: 
n=6, H=6, X=1 
DU = (2(6)+2-6-1)/2 = 3

Therefore, compound I and III have the same degree of unsaturation, and the answer is B.

Which of the Following Compounds Have the Same Degree of Unsaturation