How do alkenes typically react with oxygen?

Alkenes typically react with oxygen through a process known as incomplete combustion. During incomplete combustion, alkenes do not burn completely and instead can produce a mixture of products, including carbon dioxide, water, and carbon monoxide, along with soot or unburnt carbon. This often results in a smoky flame, indicative of insufficient oxygen for complete combustion.

In contrast, complete combustion would mean that all the carbon in the alkene is converted to carbon dioxide and all the hydrogen to water, which is not the case in many conditions where alkenes are burned. While alkenes can indeed undergo complete combustion under ideal conditions, such as ample oxygen supply, the more common observation, especially when oxygen is limited, is the incomplete combustion which creates that characteristic smoky flame.

Other options do not accurately represent the behavior of alkenes with oxygen; for example, saying they do not react with oxygen mischaracterizes their chemistry since alkenes are quite reactive in the presence of oxygen. Similarly, the notion of producing carbon monoxide only overlooks the formation of other potential products such as soot or carbon dioxide, making it an incomplete representation of their combustion behavior.