[ noun ] (chemistry) a chemical substance that is present at the start of a chemical reaction
Used in print(Francis J. Johnston and John E. Willard, "The...)
The reactants for the gas phase experiments were first frozen_out in a side arm attached to the manifold and then allowed to distill slowly into the manifold of pre-cooled reaction cells before sealing_off .
This method in_general solved the problem of obtaining fairly equal concentrations of reactants in each of the six cells from a set .
Carrier * * f was added and the aqueous and organic phases were separated ( cells containing gaseous reactants were immersed in liquid_air before opening under sodium_iodide ) .