Answer:
They are strong intermolecular forces
Explanation:
Covalent forces are very strong intermolecular forces. In fact, we can say they are the strongest. This is because several big and giant molecules have covalent bonds holding their molecules together. A good example of this is the buckministerfullerence molecule which contains carbon atom to the order of 60 carbon atoms. It is a very giant molecule and it is covalent bond that is holding the molecules together
The strongest substance in the world is diamond. It is so strong that no other substance can cut it asides another diamond. As strong as it is, the molecule is held together by very strong intermolecular forces of covalent bonds which confers the strength it has on it
Cumulene is an alkene hydrocarbon that has two or three double bonds. It is also known as allene. The simplest cumulene is butatriene. It is a rigid hydrocarbon due to the presence of double bonds.
Answer: The orbital that overlap are p/p overlap, s/sp2 overlap, sp/sp2 overlap and sp/sp orbital.
You did not include the list but F is fluorine. The first halogen.
So, you can expect that the other members of the same group (halogens, column 17 of the periodic table) exhibit similar chemical behavior (reactivity).
So, I am sure your list contains one or more of theses elements: Cl (chlorine), Br (bromine), and I (iodine).
All of them you can expect to also be reactive non metal.