In a water molecule, the bond angle between the two O-H bonds is 104.5° and the dipole moment (known as the bond dipole moment) is about 6.17 × 10-30 C∙m
[Note: The SI unit of dipole moment, the coulomb-metre is too large at molecular level. Hence, bond dipole moments are commonly expressed in the CGS unit, the debye (D); 1 D = 3.335 × 10-30 C m. So, the bond dipole moment of a water molecule is 1.85 D while that of HF, NH3 and HCl are 1.82 D, 1.47 D and 1.08 D, respectively.]
