Since only one factor changed in this experiment it is called a

A hypothesis that is tested with the manipulation of one variable, that is referred to as a controlled experiment. The change that comes from the manipulation creates a causality that is formed through cause-and-effect that is directional. The variable that is been up late it is called the independent variable, and the researcher is focused on observing the reaction of the variable that is left unaltered, and referred to as the dependent variable.

It will appear as o2(g) as a reactant