Organic Chemistry

London dispersion forces are the weak intermolecular attractive forces that occur when the molecules are spaced closely. If the spacing is compact, the interactions are stronger. This means that the temporary dipoles induced due to the dispersion of electrons are also larger. Such a compact cluster will require more energy to break, raising the physical properties of the melting and boiling point.

The longest carbon chain is the parent chain containing the principal functional group. 

The principle functional group is always given the highest priority, lowest number (1 before 2, 3, 4...), and assigned as a suffix while writing the nomenclature. Therefore, the numbering of the parent chain always starts from the principal functional group.

Hydrogen bonding is a type of electrostatic interaction occurring in molecules in which the H atom is sandwiched between highly electronegative atoms like F, O, and N, one to which it is covalently bonded. For example, HF, H₂O, NH₃, etc.