Question

Which of the following is true for the molecule O=C=S?

a. O=C=S is nonpolar because it contains only double bonds.
b. O=C=S is nonpolar because it is linear.
c. O=C=S is polar because it has a bent shape.
d. O=C=S is polar because the polarities of the O=C and C=S do not cancel.

Answer 1

The molecule O=C=S is nonpolar because it has a linear geometry, allowing the bond dipoles to cancel out, resulting in no net dipole moment.

Step-by-step explanation:

The molecule O=C=S (carbonyl sulfide) is indeed nonpolar. This is because it has a linear molecular geometry, similar to CO₂, where the bond moments of the polar double bonds cancel each other out. The accurate statement is b. O=C=S is nonpolar because it is linear. Despite having polar bonds, the symmetric, linear geometry of the molecule results in an overall nonpolarity.

If the molecule were to have a bent structure like water (H₂O), it would be polar because the bond moments would not cancel out. However, because O=C=S is linear, the polarities of the O=C and C=S bonds do indeed cancel.