Calculate the degree of unsaturation for the following molecules: Molecule I: C₃H₄ Molecule II: C₅H₁₀ Molecule III: C₄H₆ A)For molecule I the degree of unsaturation is 2,for molecule II the degree of unsaturation is 1 and for molecule III the degree of unsaturation is 1. B)For molecule I the degree of unsaturation is 2,for molecule II the degree of unsaturation is 0 and for molecule III the degree of unsaturation is 2. C)For molecule I the degree of unsaturation is 2,for molecule II the degree of unsaturation is 1 and for molecule III the degree of unsaturation is 2. D)For molecule I the degree of unsaturation is 2,for molecule II the degree of unsaturation is 2 and for molecule III the degree of unsaturation is 2. E)For molecule I the degree of unsaturation is 1,for molecule II the degree of unsaturation is 2 and for molecule III the degree of unsaturation is 1.

Question

Quizplus · Accepted Answer

The degree of unsaturation is calculated using the formula [(2n + 2) - x]/2 where n is the number of carbons and x is the sum of the hydrogens and halogens. 
For molecule I, n=6 and x=11, so degree of unsaturation = [(2*6 + 2) - 11]/2 = 2 
For molecule II, n=7 and x=111, so degree of unsaturation = [(2*7 + 2) - 111]/2 = 1 
For molecule III, n=6 and x=16, so degree of unsaturation = [(2*6 + 2) - 16]/2 = 2 
Therefore, the best choice is C, where I has a degree of unsaturation of 2, II has a degree of unsaturation of 1, and III has a degree of unsaturation of 2.

Calculate the Degree of Unsaturation for the Following Molecules