What peak on the above MS spectrum of the molecule provides information about the molecular mass of the compound? What fragment does it belong to? Justify your answer. The peak at m/z84. Its value is the same as the molecular weight of the provided formula. It belongs to the molecular ion which results from the original molecule losing one electron. The peak at m/z41. It is the largest peak indicating the most stable fragment of the original molecule. The peak at m/z84. Its value is the same as the molecular weight of the provided formula. It belongs to the molecular ion which results from the original molecule gaining one electron. Rel. Intensity What fragmentation does the peak at m/z69 represent? What justifies its size? Answer: Loss of a CH3 negative fragment by the molecular ion. The peak represents a charged fragment containing an allylic cation that is stabilized by resonance. Answer: Loss of a C5H9 neutral fragment by the molecular ion. The peak represents a charged fragment containing an acylium cation that is stabilized by hyperconjugation. Answer: Loss of a CH3 neutral fragment by the molecular ion. The peak represents a charged fragment containing an allylic cation that is stabilized by resonance