Which molecules have an overall dipole moment?1. Carbon Monoxide, CO 2. Phosphine, P{H_3} 3. carbon dioxide, C{O_2} (A) 1,2,3 are correct(B) 1 and 2 only are correct(C) 2 and 3 only are correct (D) 1 only is correct

To determine whether a molecule has an overall dipole moment, we need to consider the polarity of its bonds and the geometry of the molecule.

Carbon Monoxide (CO): Carbon monoxide has a polar covalent bond between the carbon and oxygen atoms, with oxygen being more electronegative than carbon. The molecule is linear in shape. Thus, it has an overall dipole moment due to the unequal sharing of electrons between carbon and oxygen.

Phosphine (PH3): Phosphine has polar covalent bonds between phosphorus and hydrogen atoms. However, the molecule has a trigonal pyramidal shape with the lone pair on phosphorus. The dipole moments of the P-H bonds do not cancel each other out due to the asymmetrical shape, resulting in an overall dipole moment.

Carbon Dioxide (CO2): Carbon dioxide has two polar covalent bonds between carbon and oxygen atoms. However, the molecule is linear, and the bond dipoles are symmetrical and cancel each other out. Therefore, even though CO2 has polar bonds, its molecular geometry results in no overall dipole moment.

Based on the analysis:

(A) 1,2,3 are correct is the correct choice.