  We study the ejecta chemistry of a zero-metallicity progenitor, massive,
supernova using a novel approach based on chemical kinetics. Species considered
span the range of simple, di-atomic molecules such as CO or SiO to more complex
species involved in dust nucleation processes. We describe their formation from
the gas phase including all possible relevant chemical processes and apply it
to the ejecta of a primordial 170 Msun supernova. Two ejecta cases are
explored: full mixing of the heavy elements, and a stratified ejecta reflecting
the progenitor nucleosynthesis. Penetration of hydrogen from the progenitor
envelope is considered. We show that molecules form very efficiently in the
ejecta of primordial supernovae whatever the level of mixing and account for 13
to 34% of the total progenitor mass, equivalent to 21 to 57 Msun of the ejecta
material in molecular form. The chemical nature of molecules depends on mixing
of heavy elements and hydrogen in the ejecta. Species produced include O2, CO,
CO2, SiS, SO, SiO and H2. Consequently, molecules can be used as observational
tracers of supernova mixing after explosion. We conclude that primordial
massive supernovae are the first molecule providers to the early universe.
