8. What affects chemical change?

pictorial diagram showing how to perform reaction

“What affects chemical change?” is a question of identification of internal and external variables that affect the extent and rate of chemical processes. The extent to which reactants are transformed into products and the rate at which the transformation occurs depend on internal factors such as the composition and structure of the particles involved and their concentration in the system, as well as on external factors such as temperature, pressure, and the nature of the environment in which the reaction takes place (e.g., type of solvent, pH). Identifying these factors and their effects on reaction extent and rate allows us to design and control chemical processes for particular purposes.


The Volcano Probe formative assessment was developed by the ACCT team (indicated by the star).

The Volcano Probe is a formative assessment tool for learning about how students think about choosing reactants and reaction conditions based on how they think about chemical control. It has been tested in middle school, high school, and university chemistry classes.