The Facts For Define
A reversible change is when you can re-do something such us a mistake in pencil you can rub it out which makes it a reversible change.
A non-reversible change is an event that cannot be changed (only reason I could think of XD) such as death you cannot re-do death like we can redo a pencil mistake.
Variables In an Experiment
The variables in an experiment are Independent, Dependant and controlled those are the variables of an experiment; the independent is the change by scientist.
The Structure of A scientific Experiment
The structure of a scientific investigation is:
Title, Abstract, Introduction, Method, Results, Discussion, Reference List and Appendices and Appendices is information that you found that is not useful for your investigation.
A Hypothesis is a theory off the limited evidence that you have in your current possession and is a start to a further investigation.
Alchemy is the medieval forerunner chemistry but it is trying to create different effects, creations or combinations by using a created elixir that they created with alchemy.