試題詳解

46. Which of the following statements about the ¹H NMR (Nuclear Magnetic Resonance) experiment is incorrect?
(A)The energy difference between the two spin states ( = +1/2 and =-1/2) depends on the strength of the magnetic field.
(B)When energy absorption takes place, the electrons are excited by the electromagnetic radiation to obtain the NMR signal.
(C) When aligned with the magnetic field, the energy of a proton with spin of mi = +1/2 is lower than that with mi = -1/2 when aligned against it.
(D) The relative population of the upper spin state, N_upper, and of the lower spin state, N_lower, is given by the Boltzmann equation (N_upper / N_lower = e^-△E/kT).
(E) The energy needed to flip the spin of a proton is within the radio frequency range of the electromagnetic spectrum.