The 13C nucleus is a spin 1/2 particle, which means it can orient in two directions in a magnetic field (with the field and against it). The difference in energy between the two orientations is given by:
?E = (0.705 x 10-26 J T-1)B
where B is the magnetic field strength in Tesla. In an NMR spectrometer with a 1.45 T field strength, what is the ratio of the population of nuclei oriented opposite the magnetic field with respect to those oriented with the magnetic field at 25 °C?