Linoleic acid is a polyunsaturated fatty acid found, in ester form, in many fats and oils. its doubly allylic hydrogens are particularly susceptible to abstraction by radicals, a process that can lead to the oxidative degradation of the fat or oil. the radical formed by abstraction of one of the doubly allylic hydrogens is an allylic radical that has three resonance structures. complete one of these resonance structures by dragging bonds and electrons to their appropriate positions.