There isn't a direct antonym for "chemical equation" in the traditional sense. It's like trying to find an antonym for "sentence" – it's a specific concept with no direct opposite.

However, you could consider these concepts that are the opposite of what a chemical equation *represents*:

* Physical Change: A chemical equation describes a chemical change (new substances are formed). A physical change, like melting ice, doesn't create new substances.

* Verbal Description: Instead of a symbolic equation, you could have a written description of a chemical reaction.

* Qualitative Observation: A chemical equation is quantitative (shows exact amounts). A qualitative observation is descriptive (e.g., "the solution turned blue").

It depends on the context you're looking for an "opposite" of.