We shall learn when we study molecular spectroscopy that heteronuclear diatomic molecules absorb radiation in the microwave region and that one determines directly the so-called rotational constant of the molecule defined by 8m21 where I is the moment of inertia ofthe molecule. Given that B = 3.13 × 1 05 MHz for H35CI, calculate the internuclear separation for H35Cl. The atomic mass of H and 35CI are 1.008 and 34.97, respectively.