Every reaction in it is checked, atom for atom.
Where one is simplified, the catalogue says how and why.

A day with it
Before work
Two reagents, one reaction, and the bench starts on its own.
At lunch
A tier opens. New reagents, so new reactions become possible.
In the evening
Back to a bench that kept going: one reaction set off the next.
What is in the catalogue
You run a chemistry lab. Each fume hood runs one reaction, and what one hood makes can feed the next, so the lab grows into chains. Over two hundred molecules with their actual formulas, and the hundred-odd reactions between them written as a chemistry teacher would write them. A dozen tiers, each opening the reagents for the next reactions. The lab keeps working while the phone is in your pocket.