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Determining a Molecular Formula

An organic compound (A) is composed of carbon, hydrogen and nitrogen, with carbon constituting over 60% of the mass. It shows a molecular ion at m/z=112 amu in the mass spectrum. Answer the following questions by entering numbers in the answer boxes.

1. Write a plausible Molecular Formula for compound A: CHN

2. How many Rings + Double Bonds must be present in compound A?

Another compound, B, composed only of carbon, hydrogen and oxygen, also shows a molecular ion at m/z=112 amu.

3. Write a plausible Molecular Formula for compound B, assuming it has three double bonds and no rings. CHO

Compound C is composed only of carbon, hydrogen and oxygen, and shows a molecular ion at m/z=180 amu. Carbon accounts for 60% of the molecular mass.

4. Write a plausible Molecular Formula for compound C. CHO

5. How many Rings + Double Bonds must be present in compound C?

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