# Maximum number of double bonds a carbon atom can make

What is the maximum number of double bonds a carbon atom can make?

Well, carbon has $4$ valence electrons so... it needs $4$ more to fulfill the octet rule right?

If a double bond yields $4$ electrons, does it mean that the carbon atom can make only one double bond?

OR does it mean it can create up to TWO double bonds (because they would yield $8$ electrons which fulfill the octet rule)?

What about Calcium? I ask because Calcium doesn't follow the Octet rule: it only wants to have 4 electrons, so...

• Calcium generally forms fairly ionic compounds so the concept of a double bond isn't necessarily applicable. In regards to carbon, each double bond gives it two more electrons, on top of those that it already has, so I'll let you figure out which answer that leaves you with. – bon Jul 16 '15 at 19:36
• Rather than focus on what it's gaining, try to draw a Lewis structure of carbon connecting to a carbon on each side. Then try changing the connections between them to different numbers and arrangements of bonds and check whether or not the central carbon has a satisfied octet. By doing this systematically you can probably "prove" the answer to yourself. – Eli Riekeberg Jul 16 '15 at 21:39