In order to discuss the question of the reduction of chemistry it will be necessary to begin with a brief review of what philosophers mean by reduction in science. I follow most authors on this subject by starting with the writings of Nagel (Nagel 1961). As is well known, Nagel stipulates that two formal conditions, namely connectability and derivability should be fulfilled in order to say that reduction of theory T2 to theory T1 has occurred. In addition he stipulates a non formal condition, that the primary or reducing science should be supported by experimental evidence.
Furthermore Nagel considers that reductions occur in two main varieties which he calls homogeneous and heterogeneous respectively. In homogeneous reduction the terms used by the reducing theory are also common to the theory to be reduced. For example Galileo's science of freely falling bodies was conceived of as separate from the mechanics of celestial bodies.