As previously mentioned, the above process requires calibration using a set of known concentrations of diluted salicylic acid in iron (III) nitrate solution. The two substances react with a 1:1 mole ratio, but since the goal of the calibration is for the salicylic acid specifically to fully react, it would be safer to have an excess of iron (III) nitrate. The different temperature values for the independent variable were chosen based on the scope of this exploration, which was to explore temperature's effect on the production of salicylic in the context of household usage. Selecting extremely high temperature values would be unrealistic for a household, which is why the lowest temperature value was chosen to be 30.0ºC, resembling the temperature of a hot summer day. 30.0°C was also chosen because it was higher than the average room temperature of 20°C and the exact temperature could therefore be achieved through the use of a hot plate (What Is the Ideal Room Temperature?, n.d.). For reference, the room temperature of the laboratory on the first day of experimentation was recorded to be 19.8°C. The independent values increase by larger increments of 15.0ºC, so they significantly affect the dependent concentration values and lead to a clearer correlation. The highest independent value is 90.0ºC, which is the maximum allowable wood cabinet temperature, again being realistic for where aspirin would be stored in a household (NE63T8111SS, n.d.).