Abstract

This chapter first evokes the objects of chemistry and the role played by experimentation in the constitution of its objects. It then studies how chemists set up experimental protocols to deal with the dependence of chemical bodies on the inert or living environments in which they are found. To this end, its pays particular attention to the preparation of reference matrices for measurement and for the validation of results. In so doing, it stresses the fact that chemists use a dizzying pluralism of instruments, procedures, reasonings, and methods in order to characterize and quantify substances, which are never truly detachable, except in the case of approximations satisfying particular objectives, from the empirical complex {apparatus-methods-chemical substances-associated medium} in which they are scrutinized.