What has a dipole-dipole force- hydrogen bond or London force?

Answer 1

Chapter 6-5? me too. anyway they are all forces of attraction used to kelp keep molecules together. Since the molecules are the atoms bonded together, there are no electrons, or not enough, left over to bond with more atoms. The result would be trillions of tiny molecules floating about. Instead, each of these types of attractions draw the molecules together into solids or liquids.

They are all intermolecular forces, meaning they are forces of attraction between molecules. They also are all helpful in explaining the physical properties of substances, such as boiling / melting point.

Answer 2

The mechanism of hydrogen bond is usually described as a special case of a (permanent)dipole (permanent) dipole interaction. London dispersion forces are caused by instantaneous dipole, induced dipole interactions between electron clouds on adjacent molecules.

So one similarity is they are dipole based.

They are also consideerd to be weak forces (weak relative to covalent bonds) but hydrogen bonding is stronger than dispersion forces

Answer 3

Wan der Waals' forces (recently called London Forces) are the weak attractions between non-polar compounds or monatomic elements. They occur because the electrons in the out energy level are moving around, so when they are near another atom's outer electrons, they attract with fairly weak forces.

Dipole-dipole attractions occur between ionic and polar compounds due to the difference in electonegativity between the atoms in the compound. For example, in hydrogen fluoride, HF, the fluorine has a higher electro negativity so most of the electrons are located around the fluorine atom, making that end of the structure slightly negative. Then, the negative side of the molecule becomes attracted to the positive end of another molecule - i.e. the end with the hydrogen atom. This happens continuously. These attractions are stronger than Van der Waals' forces.

Hydrogen bonding only occurs in compounds containing a fluorine, oxygen, or nitrogen atom, bonded to a hydrogen atom. This can be remembered by Freak Of Nature. They occur because the hydrogen loses its electron completely as it is not very electronegative. Thus, it makes that part of the molecule positively charged, and like the dipole-dipole attractions, it is attracted to the oppositely charged atoms of another molecule. A good example is water, H20. It has oxygen bonded to hydrogen, so it has hydrogen bonding between the molecules. The oxygen atom becomes slightly negative and the hydrogen atoms positive. Then, the oxygen becomes attracted to a hydrogen atom of another atom and so on. These are the strongest of all intermolecular forces, and this is why water has an unexpectedly high boiling point; because the hydrogen bonds need to be broken.

So the weakest is Van der Waals' (London forces), then dipole-dipole attractions, and the strongest of all which is hydrogen bonding.

Hope this helped!

Answer 4

theyre both strong but hydrogen is stronger

Answer 5

both are formed due to some opposite charges on the elements

Answer 6

NH3 due to its shape