Question

Why do alkenes burn with a sooty flame?

Answer 1

Answer:

they burn with a sooty flame due to incomplete combustion of saturated hydrocarbon in the air .

Explanation:

Answer 2

Answer   :

The alkenes burns with a highly-sooty flame, producing thick, black smoke. This happens because of incomplete combustion of the saturated hydrocarbon in the air.

The flame is sooty because the percentage of carbon is comparatively higher than that of alkanes and so does not get completely oxidized in air.

hope it will help.........