Unsolved problems in chemistry tend to be ("can we make X compound") and are solved rather quickly, but here are some persistent questions with deep implications: * Solvolysis of the norbornyl cation: Why is the norbornyl cation so stable? Is it symmetrical? This problem has been largely settled for the unsubstituted norbornyl cation, but not for the substituted cation. * On-water reactions: Why are some organic reactions accelerated at the water-organic interface? * Better-than perfect enzymes: Why do some enzymes exhibit faster-than-diffusion kinetics? * Feynmanium: What are the chemical consequences of having an element (137) whose electrons must travel faster than the speed of light? * Chemical transformation traversal: Is it practical to generate a database of chemic