O=C=O molecule is linear so that the polarities of two C – O bonds get cancelled and the molecule is linear.
Ethers have structures similar to water and have angular or bent structure. Therefore, the polarity of two R – O groups does not get cancelled and these have net dipole moment. Thus, R – O – R is polar.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.