Which ion will show the least deflection in a mass spectrometer?

A.     $^{{\text{35}}}{\text{C}}{{\text{l}}^ + }$

B.     $^{{\text{35}}}{\text{C}}{{\text{l}}^{2 + }}$

C.     $^{{\text{35}}}{\text{C}}{{\text{l}}^{{\text{35}}}}{\text{C}}{{\text{l}}^ + }$

D.     $^{{\text{35}}}{\text{C}}{{\text{l}}^{{\text{37}}}}{\text{C}}{{\text{l}}^ + }$

D

We recognize that students might have found the molecular ions confusing. The question was answered correctly by 49.8% of the candidates and the question discriminated well (0.48). This is an example of a question set to discriminate the higher-grade candidates.