Examples of Variables and Responses for a Chemical Process
Examples of Variables and Responses for a Chemical Process
Table 1 provides examples of the types of variables and responses for a chemical process. A continuous variable is a factor whose values can easily be adjusted over a range (quantitative factor). A categorical variable is a factor that is non-continuous (qualitative factor).
Table 1
Variables
Responses
Continuous
Categorical
Substrate A/B ratio
Substrate A/ Substrate B
Conversion
Reagent quality
Regioselectivity
Temperature
Stereoselectivity
Concentration
Reagent
Enatioselectivity
Rate of addition
Solvent
Rate or rate constant
pH
Order of addition
Purity / impurities
Time
Type of equipment
Isolated yield
Pressure
Particle size
Agitation rate
Density
When selecting factors to study, use prior knowledge where available (previous observations, literature knowledge, related chemistry, etc.) and choose factors that are likely to answer the experimental objectives.
