Question

Amines with an odd number of ____________ atoms give an odd molecular ion in their mass spectra.

Answer 1

Amines with an odd number of Nitrogen atoms give an odd molecular ion in their mass spectra.

I have attached four examples of such amines,

Amines containg 1 and 3 number of Nitrogen Atoms give Odd Molecular Ion in their Mass spectra.
And,
Amines containg 2 and 4 number of Nitrogen Atoms give Even Molecular Ion in their Mass spectra.