A molecule of, CO, a diatomic molecule, is made up of a carbon atom (mass = 12u) and an oxygen atom (mass = 16u), separated by a distance r. It is assumed that the rotational K.E, of the molecule, about its centre of mass, is quantized as per Bohr’s postulates for the hydrogen atom. If the frequency of the photon, that can excite the molecule from its (rotational kinetic energy) ground state to its first excited state is (4/π x 10 Hz) (and the Planck’s constant equals 2π x 10-34 J – s), the distance r, and the moment of inertia, I, of the molecule, about its centre of mass, are (nearly) equal, respectively, to
(1) 11.28 x 10-10 m and 1.88-46 10 kg - m2
(2) 2.4 x 10-10 m and 2.76-46 kg - m2
(3) 4.4 x 10-11 m and 4.67 10-47 kg - m2
(4) 1.9 x 10-10 m and 1.17 x 10-47kg - m2