The first bond between two atoms is always a sigma bond and the other bonds are always pi bonds and a hybridized orbital cannot be involved in a pi bond. Thus we need to leave one electron (in case of Carbon double bond) to let the Carbon have the second bond as a pi bond.
Its just like backing soda and viniger i think hope that helped
Answer:
The electrochemical phenomenon of rusting of iron can be described as : At Anode: Fe (s) undergoes oxidation to releases electrons. Electrons released at anode move to another metal and reduce oxygen in presence of H+. It is available from H2CO3 formed from the dissolution of CO2 from air into water.
