This study applied a factorial experimental design to study the influence and interaction of the variables for the synthesis of CuO NPs. A 3 k full factorial planning matrix was defined using the values and coded levels provided in Table . Thus, based on the preparation procedure, the independent variables selected were reaction temperature and mass of Cu(II) nitrate trihydrate, Cu(NO3)2•3H2O. The response factor in the factorial design was the product conversion yield (PCY).