JEE Main levelSingle correct optionDifficulty 2 of 3si074
Which of the following has a molecular ion at an odd m/z value (use X12X2212C, X1X221H, X14X2214N, X16X2216O)?
ACX3HX8O
BCX3HX9N
CCX2HX4OX2
DCX4HX10
Answer: B
Masses: CX3HX9N = 59, CX3HX8O = 60, CX2HX4OX2 = 60, CX4HX10 = 58. Only the compound with one (odd number of) nitrogen has an odd molecular mass, as the nitrogen rule states.