Elements of Unsaturation Unsaturation:A structural element that decreases the number of hydrogens in the molecule by two. Double bonds and rings are elements of unsaturation. To calculate:Find number of hydrogens if they were saturated,subtract the actual number of hydrogens,then divide by 2. Chapter 7 8 Chapter 7 8 Elements of Unsaturation • Unsaturation: A structural element that decreases the number of hydrogens in the molecule by two. • Double bonds and rings are elements of unsaturation. • To calculate: Find number of hydrogens if they were saturated, subtract the actual number of hydrogens, then divide by 2