It was typically taught that physical changes are differentiated from chemical changes because they could be “undone” or that they had “no chemical reaction.” Which was very confusing, because you can’t uncut paper, and dissolving stuff in water clearly results in different chemicals being produced, yet both were examples of physical changes (actually the latter is sometimes taught as a chemical change). Furthermore, most chemical changes are actually reversible.
It has since been recognised that this classification is BS, and most changes actually exist on a continuum.
I am teaching this next week. It is sometimes painful how simplified we have to make content for middle school. You are expressing what science teachers hope for from students. You were curious enough to explore further and ask questions, the true purpose of science.
Physical Vs chemical changes.
It was typically taught that physical changes are differentiated from chemical changes because they could be “undone” or that they had “no chemical reaction.” Which was very confusing, because you can’t uncut paper, and dissolving stuff in water clearly results in different chemicals being produced, yet both were examples of physical changes (actually the latter is sometimes taught as a chemical change). Furthermore, most chemical changes are actually reversible.
It has since been recognised that this classification is BS, and most changes actually exist on a continuum.
I distinctly remember my fifth grade teacher trying to pull that.
I am teaching this next week. It is sometimes painful how simplified we have to make content for middle school. You are expressing what science teachers hope for from students. You were curious enough to explore further and ask questions, the true purpose of science.