How can a non-polar trigonal molecule become a polar molecule?

Answer 1

If the trigonal molecule (as ocurrs in a double bonding in most hydrocarbons) suffers the attack from a reactive chemical agent, the geometry of the atom that supports the bonding can change to a tetrahedrical conformation with an available electronic pair or electronegative atom (it depends on the reactive agent) that can generate a dipolar moment and this way becoming a polar molecule.

For example, an alkene (not polar and with trigonal geometry) attacked with acid and an oxidant agent can yield two molecules of carboxilic acid or alcohol which are both of them, polar molecules.

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