Analytes Must Be Ionized Prior to Entering the Mass Filter

question 10

Multiple Choice

Analytes must be ionized prior to entering the mass filter in a mass spectrometer.Electron ionization and chemical ionization are two ionization techniques.Which of the following statements are INCORRECT regarding either technique?
I Electron ionization uses an electron beam to create molecular ions,M^+.
II Chemical ionization uses an electron beam to ionize reagent gas.
III Electron ionization gives very little fragmentation of the molecular ion.
IV The ionized reagent gas in chemical ionization undergoes a complex set of chemical reactions before protonating the analyte to create MH⁺.
V Both ionization techniques give identical mass spectra.

• A)I,III,and V
• B)III and V
• C)II,III,and IV
• D)I,II,and IV
• E)I,II,and V

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