In a typical mass spectrum, a smaller signal is observed at a mass 1 amu higher than the molecular ion peak.Why?

Question

Quizplus · Accepted Answer

The peak observed at 1 amu higher than the molecular ion peak is due to the presence of a minor isotopic form of carbon, ¹³C instead of the more common ¹²C. This peak is known as the M+1 peak and is commonly observed in mass spectra. It is not due to impurities, machine error, or fragmentation.

In a Typical Mass Spectrum, a Smaller Signal Is