Van der waals interactions result when hybrid orbitals overlap. a hydrogen atom loses an electron. molecules held by ionic bonds react with water. two polar covalent bonds react. electrons are not symmetrically distributed in a molecule.

Van der waals interactions are the electrical interactions between two or more atoms and even molecules but the inter-molecular attractions between the molecules are not exactly strong, in fact they are the weakest. And these Van der waals interactions are happened when electrons are not symmetrical distributed in a molecule.

Answerd. may include all of these are many definitions of bases: the  brønsted-lowry definition of acids and bases says that bases are proton acceptors.the arrhenius definition of acids and bases says that bases increase [oh⁻] in solution (thereby producing oh⁻ ions)the lewis definition of acids and bases says that bases donate electron pairs.therefore, the sensible answer is that a base may include all of the described characteristics.