What is the name of this molecule?
answer choices given with my guess.

None of the above. It’s 5-ethyl-3-octene because the longest possible chain contains 8 carbon atoms and alkene gets priority in naming and you want to give the lowest possible number to the position of the double bond regardless of the placement of the substituent.

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of carbon is as shown here in the image.

dynamic equilibrium is the answer.