Summarize the steps of the scientific method. what is the purpose of the control in an experiment? the variable?

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.