Nootkatone one of the chemicals responsible for the odour and taste of grape fruit, shows a molecular ion a M/E= 218 in its mass spectrum and contains carbons, hydrogen, and oxygen.

Suggest several possible molecular formular for nootkatone. How many degrees of unsaturated (double bonds & rings) are indicated.

Use the following information to propose a molecular formula for nootkatone a compound partly responsible for the characteristic odor of grapefruit. Nootkatone contains the elements C, H, and O has five degrees of unsaturation and a molecular ion in its mass spectrum at m/z=218. 

Nootkatone is an unsaturated ketone found in grapefruit. If Nootkatone has M+ = 218 and contains 3 double bond(s) and 2 ring(s); what is its molecular formula? Please explain in detail how you got the answer.

An organic compound A is composed of carbon, hydrogen andnitrogen, with carbon constituting over 60% of the mass. It shows amolecular ion at m/z= 112 in the mass spectrum.

1. Write a plausible molecular formula for compound A
2. How many rings + double bonds must be present in compoundA?