The following are some statements about dipole moment.
i) The dipolemoment of any covalent molecule is zero
ii) The dipolemoment of a diatomic molecule having non–polar bonds is zero
iii) The dipolemoment of a diatomic molecule having polar covalent bond is non–zero.

(i) Dipole moment of any covalent molecule is zero .........false.
    A covalent molecule can be polar (or) non-polar
(ii) Dipole moment of homodiatomic molecule is zero ......true
    μ of H₂,X₂,N₂,O₂ is zero.
(iii) Dipole moment of hetero diatomic molecule is non- zero ......true
    μ of NO,CO,HX,O₂ is zero.