The scientist who discovered radioactivity was: MCQ with Answer and Explanation

Explanation:
Carbon monoxide (CO) has a triple bond. In the formation, oxygen, with two lone pairs, donates one lone pair to form a coordinate bond with carbon after normal double bond formation, resulting in a structure :C≡O:. Thus oxygen donates the pair. This satisfies the octet for both.

Explanation:
CO₂ is a linear molecule (O=C=O). Although the C=O bonds are polar, the molecule is symmetric, and the dipole moments of the two bonds are equal and opposite, canceling each other out. Thus, the net dipole moment is zero, making it non-polar. HCl, H₂O, and NH₃ are polar.

Explanation:
A promoter is a substance that, when added in small quantities, enhances the activity or efficiency of a catalyst. For example, in the Haber process, molybdenum acts as a promoter for the iron catalyst. An inhibitor or poison decreases catalyst activity by blocking active sites.