Respuesta :
I believe the correct answer from the choices listed above is the second option. A molecule of alkene has the chemical formula C3H4. From teh formula, we can say that the number of carbon-carbon double bonds are in the molecule should be two. The four hydrogen atoms are attached in each of the end carbon atoms. These carbon atoms have two hydrogen atoms attached to them.
Answer : Option A) 2
Explanation : The molecule [tex] C_{3} H_{4} [/tex] has two carbon-carbon double bonds. The reference image is attached below. The four hydrogen atoms are attached to the two terminal carbon atoms. Three carbon are connected to each other by two double bonds (C=C=C) and the hydrogen bond has a single bond attached to the carbon (C-H). An alkene will always have a double bond in its structure. Also, [tex] C_{3} H_{4} [/tex] is called as an allene.