The 5 branches are organic, inorganic, biochemistry, analytical, and physical. There are different branches because they each apply to different parts of chemistry. For example organic chemistry is the study of carbon compounds and inorganic chemistry is the study of non carbon compounds. You can't just have one type of chemistry because these are very different.
answered: Guest
vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.