Initial Model-based Explanation

1.A Develop a model showing what is happening at a scale smaller than we can see (patterns) to help explain what happened to the matter in the solid bath bombs (matter) and what caused the gas bubbles to appear (matter).

This first model students develop on What Happens to a Bath Bomb When Put in Water? is more representative of what they see happening with the bath bomb at a macrosopic level. Therefore the particle level representations may not be included at all, or may be minimally included. They will develop a second model of this at a microscopic, or particle level next in Initial Model-based Explanation. Look for the following elements across their models and explanations to see if they bring these ideas to the table with the prompts for the task as written:

Unobservable mechanisms labeled/referenced for two aspects of the phenomenon: Changes in the solid: through a process such as melting, dissolving, or reacting/interacting with other materials. Appearance of a gas: through a process such as the “release of a gas” from pockets in the solid, evaporation, boiling, or a new substance being produced that wasn’t there before from some of the matter that we started with.